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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Finance lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeilleurTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Meilleur Technologies, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeilleurTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Meilleur Technologies, Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeilleurTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Meilleur Technologies, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Revenue Discount Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement input revenue discount rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares issued (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Inventory, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Change in Contingent Consideration, Liability, Increase (Decrease)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in fair value included in net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockAcquiredAverageCostPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Acquired, Average Cost Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level&#160;2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfSalary_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Salary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfSalary_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Salary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfSalary_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of salary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Stated Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Percentage of annual interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue from Contract with Customer [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedLicensedAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Radiopharm Theranostics Limited, Licensed Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedLicensedAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Radiopharm Theranostics Limited, Licensed Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedLicensedAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Radiopharm Theranostics Limited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredIncludingEquityInterestInAcquireeHeldPriorToCombination1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred and Preacquisition Equity Interest in Acquiree</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredIncludingEquityInterestInAcquireeHeldPriorToCombination1_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Consideration Transferred and Preacquisition Equity Interest in Acquiree, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredIncludingEquityInterestInAcquireeHeldPriorToCombination1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Component of consideration transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average common shares outstanding:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Maturities of Long-Term Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Maturities of Principal Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCashPurchasePriceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Cash Purchase Price [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCashPurchasePriceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred cash purchase price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCashPurchasePriceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Cash Purchase Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lantheus Holdings, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lantheus Holdings, Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lantheus Holdings, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue from Contract with Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer Benchmark [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2031 and thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets Amortization Expense After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finite lived intangible assets amortization expense after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset obtained in exchange for operating lease obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Businesses, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments to acquire businesses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Deposit for acquisition of a business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deposit for acquisition of a business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase price percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LifeMolecularImagingLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Life Molecular Imaging Ltd</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LifeMolecularImagingLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Life Molecular Imaging Ltd [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LifeMolecularImagingLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Life Molecular Imaging Ltd</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock remain available for repurchase</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Acquiree [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition, Acquiree [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_A1404CommercializationMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">1404 Commercialization Milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Intangible Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Current Maturities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetsLiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNetOfTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets Liabilities Of Disposal Group Including Discontinued Operation Net Of Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetsLiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNetOfTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assets liabilities of disposal group including discontinued operation net of transaction costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetsLiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNetOfTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying value of the deconsolidated assets and liabilities, net of transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Percentage of Voting Interests Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of acquired interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money market funds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ExtinguishmentOfDebtAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Extinguishment of Debt, Amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetLeverageRatioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net Leverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetLeverageRatioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Leverage Ratio [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetLeverageRatioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Leverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Goodwill, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Goodwill, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Noncash Income (Expense)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Common, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Treasury stock at cost; 7,241 shares at March 31, 2026 and December 31, 2025, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationAccretionExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligation, Accretion Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationAccretionExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accretion expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisition of exclusive license option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisition of exclusive license option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EBITDADiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBITDA Discount Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EBITDADiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EBITDA discount rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EBITDADiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EBITDA discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentToDisposeABusinessRegardingRelatedPartyTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment To Dispose A Business Regarding Related Party Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentToDisposeABusinessRegardingRelatedPartyTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment To Dispose A Business Regarding Related Party Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentToDisposeABusinessRegardingRelatedPartyTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment to dispose a business regarding related party transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ContingentConsiderationAssetsRelatedToSaleOfBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Assets Related to Sale of Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ContingentConsiderationAssetsRelatedToSaleOfBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent consideration assets related to sale of business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ContingentConsiderationAssetsRelatedToSaleOfBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent consideration assets related to sale of business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupCarryingValueOfDeconsolidatedAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying value of deconsolidated assets and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupCarryingValueOfDeconsolidatedAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Carrying Value of Deconsolidated Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupCarryingValueOfDeconsolidatedAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal group carrying value of deconsolidated assets and liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevisionOfEstimatesDecommissioningCostsRelatedToAssetRetirementObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revision Of Estimates Decommissioning Costs Related To Asset Retirement Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevisionOfEstimatesDecommissioningCostsRelatedToAssetRetirementObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision Of Estimates Decommissioning Costs Related To Asset Retirement Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevisionOfEstimatesDecommissioningCostsRelatedToAssetRetirementObligations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Revision of estimated decommissioning costs related to asset retirement obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Inventory, Current [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CardiologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cardiology [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CardiologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cardiology.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CardiologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total cardiology</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Useful Life</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment, Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basic income per common share (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeurologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Neurology [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeurologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Neurology.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeurologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total neurology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Disaggregation of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLongTermDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments of long-term debt and other borrowings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Benefits [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Benefit Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMaximumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent regulatory and development milestones maximum amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMaximumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease In The Contingent Regulatory And Development Milestones Maximum Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMaximumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Decrease In The Contingent Regulatory And Development Milestones Maximum Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Including Discontinued Operation Asset Retirement Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset retirement obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal group including discontinued operation asset retirement obligation current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal Group, Including Discontinued Operation, Right Of Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Right Of Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right of use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashOnEarlierOfJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash on Earlier of January 1, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashOnEarlierOfJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash on Earlier of January 1, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashOnEarlierOfJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash on Earlier of January 1, 2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility, accordion feature, higher borrowing capacity option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net income to net cash flows from operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Research and Development Costs, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Research and Development Costs, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EntityWideRevenueMajorCustomerLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Major Customer [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputProbabilityOfPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Probability of Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputProbabilityOfPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement input probability of payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputProbabilityOfPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability of payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Finished Goods, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finished goods</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesDeductions_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments or credits made during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesDeductions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessAcquisitionSharesAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Acquisition, Shares Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessAcquisitionSharesAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Shares Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessAcquisitionSharesAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares acquired (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForPreviousAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Previous Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForPreviousAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments for prior acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current and noncurrent liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquitySecuritiesFvNi_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Equity Securities, FV-NI</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquitySecuritiesFvNi_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of investment in equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' Equity and Stock-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of convertible notes (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RelatedPartyTransactionCostRegardingTheSaleOfBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Related Party Transaction Cost Regarding The Sale Of Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RelatedPartyTransactionCostRegardingTheSaleOfBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction cost related to sale of business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceMinimumInterestCoverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, Covenant Compliance, Minimum Interest Coverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceMinimumInterestCoverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Covenant Compliance, Minimum Interest Coverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceMinimumInterestCoverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum interest coverage ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets held-for-sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets held for sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities and Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantLeverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, Covenant Leverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantLeverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Covenant Leverage Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantLeverageRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, covenant leverage ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, redemption price, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OtherNonoperatingIncomeExpenseMiscellaneous_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other Nonoperating Income (Expense), Miscellaneous</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OtherNonoperatingIncomeExpenseMiscellaneous_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense), Miscellaneous</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OtherNonoperatingIncomeExpenseMiscellaneous_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OtherNonoperatingIncomeExpenseMiscellaneous_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Inventory, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Significant Accounting Policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: accumulated depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusBiosciencesLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lantheus Biosciences Ltd</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusBiosciencesLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lantheus Biosciences Ltd. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LantheusBiosciencesLtdMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lantheus Biosciences Ltd. Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Measurement Input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability measurement input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Scenario1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Scenario 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Scenario1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Scenario1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostDepreciationAmortizationAndDepletion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost, Depreciation, Amortization and Depletion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostDepreciationAmortizationAndDepletion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_UnsecuredPromissoryNoteReceivableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unsecured promissory note receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_UnsecuredPromissoryNoteReceivableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unsecured Promissory Note Receivable Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_UnsecuredPromissoryNoteReceivableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unsecured Promissory Note Receivable Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, stock price percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income per common share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill and Intangibles, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceNumberOfFinancialCovenants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, Covenant Compliance, Number Of Financial Covenants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceNumberOfFinancialCovenants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Covenant Compliance, Number Of Financial Covenants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantComplianceNumberOfFinancialCovenants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of covenants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalRemainingPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Remaining Payments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalRemainingPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional remaining payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalRemainingPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Remaining Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gross Profit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gross profit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevenueFromContractWithCustomerNumberOfProductCategories_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue from Contract with Customer, Number Of Product Categories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevenueFromContractWithCustomerNumberOfProductCategories_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer, Number Of Product Categories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RevenueFromContractWithCustomerNumberOfProductCategories_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of product categories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase in cash, cash equivalents and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive securities excluded from diluted net income per common share (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupClassificationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Classification [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Deferred Tax Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BaseRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Base Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BaseRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Base Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Contingent Consideration, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Asset Acquisition, Contingent Consideration, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationSeparatelyRecognizedTransactionAcquisitionRelatedCostExpensedStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Separately Recognized Transaction, Acquisition-Related Cost, Expensed, Statement of Income or Comprehensive Income [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoThousandTwentyFourSharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand Twenty Four Share Purchase Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoThousandTwentyFourSharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Share Purchase Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoThousandTwentyFourSharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty four share purchase program.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputEbitdaMultipleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, EBITDA Multiple [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputEbitdaMultipleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EBITDA volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Accrued Expenses and Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, recognized identifiable assets acquired and liabilities assumed, accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherSundryLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Sundry Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherSundryLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SPECTBusinessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SPECT Business [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SPECTBusinessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">SPECT business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SPECTBusinessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SPECT</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedTranslationAdjustmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Currency Translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Sales [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of goods sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ownership [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ownership [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Long-term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LegalMattersAndContingenciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Matters and Contingencies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LegalMattersAndContingenciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Relationships [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer relationships</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Consecutive Trading Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold consecutive trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EquityMethodInvesteeNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentOwnedBalanceShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Owned, Balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentOwnedBalanceShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares owned (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares outstanding (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SPECT Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of dilutive share based compensation (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized in relation to the beginning of the year contract liability balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Shares withheld to cover taxes (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligation Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Retirement Obligation Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Revenue Volatility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MeasurementInputRevenueVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement input revenue volatility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock-Based Compensation Expense Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses, and Other Current and Long-Term Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetContingentConsiderationReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Contingent Consideration Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetContingentConsiderationReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Contingent Consideration Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetContingentConsiderationReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net contingent consideration receivable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Unamortized Discount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accumulated Other Comprehensive Loss</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury stock, shares (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Contingent Consideration [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetAcquisitionsNumberOfAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset Acquisitions, Number Of Assets Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetAcquisitionsNumberOfAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisitions, Number Of Assets Acquired</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DanielNiedzwieckiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Daniel Niedzwiecki</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Groups, Including Discontinued Operations [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Carrying Amounts of Assets and Liabilities Held for Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Consideration Transferred, Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset acquisition, additional milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Short-term contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LeaseModification_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease Modification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LeaseModification_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Modification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LeaseModification_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Modification of lease agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MachineryEquipmentAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Machinery Equipment And Fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MachineryEquipmentAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Machinery Equipment And Fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MachineryEquipmentAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Machinery, equipment and fixtures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Perspective Therapeutics, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Perspective Therapeutics, Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Perspective Therapeutics, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation to amounts within the condensed consolidated balance sheets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Property, Plant and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, plant and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Fair Value Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Receipt of notes related to sale of business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Notes Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total identifiable assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product revenue, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMinimumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent regulatory and development milestones minimum amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMinimumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease In The Contingent Regulatory And Development Milestones Minimum Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMinimumAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Decrease In The Contingent Regulatory And Development Milestones Minimum Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationPlanAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationPlanAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Plan Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash included in other long-term assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from employee stock purchase plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 15)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockRepurchasedDuringPeriodValueNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of common stock net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockRepurchasedDuringPeriodValueNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period Value Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockRepurchasedDuringPeriodValueNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock repurchased during period value net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, plant&#160;and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CollaborationPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CollaborationPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Payments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CollaborationPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Common Stock One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of common stock one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock one</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Work in Process, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Work in process</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt and Lease Obligation, Including Current Maturities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, basis rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SHINESPECTMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SHINE SPECT Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SHINESPECTMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">SHINE SPECT</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SHINESPECTMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SHINE SPECT</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Goodwill [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Change in Carrying Value of Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAmortizationAndAccretionNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Amortization and Accretion, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAmortizationAndAccretionNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation, amortization and accretion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal Group, Including Discontinued Operation, Right Of Use Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Right Of Use Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right of use liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BridgeLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bridge Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BridgeLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bridge Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Common Stock Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of common stock four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Perspective Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Perspective Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Perspective Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Short-TermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Short-TermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short-Term Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Short-TermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalExpendituresIncurredButNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Expenditures Incurred but Not yet Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalExpendituresIncurredButNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additions of property, plant&#160;and equipment included in liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities held for sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities held-for-sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FinancialAssuranceInFormOfSuretyBond_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the amount of financial assurance given in the form of surety bond.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FinancialAssuranceInFormOfSuretyBond_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Assurance In Form Of Surety Bond</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FinancialAssuranceInFormOfSuretyBond_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial assurance in form of surety bond</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RM2SublicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">RM2 Sublicense Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RM2SublicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">RM2 Sublicense Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RM2SublicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RM2 Sublicense Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basic weighted-average common shares outstanding (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromExternalCustomersByGeographicAreasTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from External Customers by Geographic Areas [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromExternalCustomersByGeographicAreasTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Revenue by Geographic Region Determined by Location of Customer or Other Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StrategicPartnershipsAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Strategic Partnerships And Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StrategicPartnershipsAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Strategic Partnerships And Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StrategicPartnershipsAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Strategic partnerships and other revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TotalStockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Total Stock Repurchased During Period Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TotalStockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Total stock repurchased during period shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TotalStockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total repurchase of common stock</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Milestone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Expense Information Used by CODM, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalMilestonePaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional Milestone Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalMilestonePaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Milestone Payments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalMilestonePaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Milestone Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Obligation expected to be incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligation, Liabilities Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Liability, Current and Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred compensation plan liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Compensation Liability, Current and Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Raw materials</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Raw Materials, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtCovenantScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Covenant, Scenario</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtCovenantScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Covenant, Scenario [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtCovenantScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Covenant, Scenario [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable Rate [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total stockholders&#8217; equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MaryAnneHeinoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mary Anne Heino</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MaryAnneHeinoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mary Anne Heino [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_MaryAnneHeinoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Mary Anne Heino</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Radiopharm Theranostics Limited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Radiopharm Theranostics Limited [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RadiopharmTheranosticsLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Radiopharm Theranostics Limited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remainder of 2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Software (Excluding Acquired in Process Cost)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Program third-party research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SamuelR.LenoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Samuel R. Leno</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SamuelR.LenoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Samuel R. Leno [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SamuelR.LenoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Samuel R. Leno</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetSalesTargetsForAzedraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net Sales Targets For Azedra</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetSalesTargetsForAzedraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Sales Targets For Azedra [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NetSalesTargetsForAzedraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Sales Targets for Azedra</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, plant and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Common [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss), Foreign Currency Transaction, before Tax</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive (loss) before reclassifications</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling and Marketing Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales and marketing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value of Financial Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodValueStockOptionsExercisedandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period, Value, Stock Options Exercised and Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodValueStockOptionsExercisedandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised and Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodValueStockOptionsExercisedandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option exercises and employee stock plan purchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentOwnedAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Owned, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentOwnedAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment owned, fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">United States</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/label">UNITED STATES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PrincipalOwedAmountRegardingImmaterialDerivativeRelatedToEarlyPotentialRepayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Principal Owed Amount Regarding Immaterial Derivative Related to Early Potential Repayment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PrincipalOwedAmountRegardingImmaterialDerivativeRelatedToEarlyPotentialRepayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Principal Owed Amount Regarding Immaterial Derivative Related to Early Potential Repayment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PrincipalOwedAmountRegardingImmaterialDerivativeRelatedToEarlyPotentialRepayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Immaterial derivative related to early potential repayment amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Expenses, Other Current and Long-Term Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncash Investing and Financing Items [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of non-cash investing and financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Discount Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Payment discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">In-process research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">In Process Research and Development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InstallmentNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Installment Note [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InstallmentNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Installment note.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InstallmentNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Installment Note</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Software and Software Development Costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Computer software</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligation Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Retirement Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other current and noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Other Operating Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Promissory Note Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Promissory Note Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Promissory note receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Building [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Buildings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationReclassificationToLiabilitiesHeldForSale_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligation Reclassification To Liabilities Held For Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationReclassificationToLiabilitiesHeldForSale_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset retirement obligation reclassification to liabilities held for sale.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationReclassificationToLiabilitiesHeldForSale_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reclassification to liabilities held-for-sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Goods and Services Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of goods sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Description and Basis of Presentation [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CerveauTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cerveau Technologies, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CerveauTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cerveau Technologies, Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CerveauTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cerveau Technologies, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Liability [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities assumed:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disposal Group Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination contingent consideration liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contingent consideration liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total contingent consideration liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Additional cash payment required</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of common stock, including excise tax (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Repurchase of common stock (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchase of common stock, including excise tax (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SellerNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Seller Note [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SellerNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Seller note.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SellerNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Seller Note</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Contingent Consideration, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance, Beginning</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance , Ending</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Indefinite-Lived Intangible Assets (Excluding Goodwill), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Indefinite-Lived Intangible Assets (Excluding Goodwill), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Non-amortizable, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-amortizable, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal amount 2.625% Convertible Senior Notes due 2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total gross property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ChangeInFairValueOfContingentAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Fair Value of Contingent Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ChangeInFairValueOfContingentAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in fair value of contingent assets and liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ChangeInFairValueOfContingentAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value of contingent assets and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Disposition of Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on sale of business, net of transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AcquiredIntangibleAssetMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired Intangible Asset Measurement Input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AcquiredIntangibleAssetMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Acquired intangible asset measurement input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AcquiredIntangibleAssetMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination, Increase (Decrease) In Acquired Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Increase (Decrease) In Acquired Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Charges incurred pursuant to acquired in-process research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total inventory, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OncologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Oncology [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OncologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Oncology.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OncologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total oncology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash, cash equivalents and restricted cash, end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash, cash equivalents and restricted cash, beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, cash equivalents and restricted cash at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Income and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Income and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Purchased for Award</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares available for issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Asset [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets acquired:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOptionQuantitativeDisclosuresTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Option, Disclosures [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOptionQuantitativeDisclosuresTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Option, Disclosures [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on sale of business, net of transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain on sale of business, net of transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ValuationTechniqueScenarioAnalysisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario analysis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ValuationTechniqueScenarioAnalysisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Technique Scenario Analysis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ValuationTechniqueScenarioAnalysisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Valuation technique scenario analysis.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Common Stock Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of common stock three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Change in Asset Retirement Obligation [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Changes in Asset Retirement Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncFullyDilutedBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Perspective Therapeutics, Inc, Fully Diluted Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncFullyDilutedBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Perspective Therapeutics, Inc, Fully Diluted Basis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PerspectiveTherapeuticsIncFullyDilutedBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Perspective Therapeutics, Inc, Fully Diluted Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ProgenicsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Progenics</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ProgenicsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Progenics</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ProgenicsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Progenics [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivableMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Promissory note receivable maturity date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivableMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Promissory Note Receivable Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PromissoryNoteReceivableMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Promissory Note Receivable Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFiveConvertibleSeniorNotesDueDecember2027Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Point Six Two Five Convertible Senior Notes Due December 2027 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFiveConvertibleSeniorNotesDueDecember2027Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Point Six Two Five Convertible Senior Notes Due December 2027 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFiveConvertibleSeniorNotesDueDecember2027Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Point Six Two Five Convertible Senior Notes Due December 2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligations, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at the ending of the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at the beginning of the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetRetirementObligationsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset retirement obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedFreightCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Carrying value as of the balance sheet date of obligations incurred through that date and payable for freight and distribution costs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedFreightCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Freight Costs Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedFreightCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Freight, distribution and operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Milestone Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payments in cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Groups, Including Discontinued Operations [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortizable, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted weighted-average common shares outstanding (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Diluted weighted-average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PYLARIFYMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PYLARIFY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PYLARIFYMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PYLARIFY [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PYLARIFYMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PYLARIFY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentConvertibleConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the initial conversion premium of as a percentage of last reported sale price of the Common Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentConvertibleConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentConvertibleConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial conversion premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rule 10b51 Arr Modified [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rule10b51 arrangement modified flag.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rule 10b5-1 Arrangement Modified</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeuraceqMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Neuraceq</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeuraceqMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Neuraceq [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NeuraceqMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Neuraceq.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ConversionAndCancellationAmountForInstallmentNote_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion and Cancellation Amount for Installment Note</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ConversionAndCancellationAmountForInstallmentNote_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion and cancellation Amount for Installment Note</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ConversionAndCancellationAmountForInstallmentNote_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion and cancellation amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of operating segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RegulatoryMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Regulatory Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RegulatoryMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_RegulatoryMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Regulatory Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssumedContingentConsiderationPiramalSPAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assumed Contingent Consideration Piramal SPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssumedContingentConsiderationPiramalSPAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assumed contingent consideration Piramal SPA.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssumedContingentConsiderationPiramalSPAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assumed contingent consideration Piramal SPA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAndAssetAcquisitionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Long-term contingent consideration liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term contingent consideration liabilities, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentOfWorkingCapitalSettlementInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of working capital settlement in business combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentOfWorkingCapitalSettlementInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment of Working Capital Settlement in Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentOfWorkingCapitalSettlementInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of working capital settlement in business combination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentOfWorkingCapitalSettlementInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NonRefundableUpfrontPaymentToAdjustTheFutureRoyaltyObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-refundable upfront payment to adjust the future royalty obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NonRefundableUpfrontPaymentToAdjustTheFutureRoyaltyObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Refundable Upfront Payment To Adjust The Future Royalty Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NonRefundableUpfrontPaymentToAdjustTheFutureRoyaltyObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non refundable upfront payment to adjust the future royalty obligations.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Amortizable, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial conversion price (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Gross (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total intangibles, net, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total intangibles, net, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InvestmentInEquitySecuritiesSharesOutstandingPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment in Equity Securities Shares Outstanding Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InvestmentInEquitySecuritiesSharesOutstandingPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment in equity securities shares outstanding percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_InvestmentInEquitySecuritiesSharesOutstandingPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ownership [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ownership [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNoteTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss) Note [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNoteTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total liabilities assumed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Liability Assumed, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disposal group consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of consideration received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Total net consideration received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase price as a percentage of principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares outstanding (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ResearchRevenueMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research Revenue Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ResearchRevenueMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research Revenue Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ResearchRevenueMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research Revenue Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Including Discontinued Operation Accrued Expenses And Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationAccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal group including discontinued operation accrued expenses and other liabilities current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FairValueOfContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value of Contingent Consideration [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FairValueOfContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair Value of Contingent Consideration [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_FairValueOfContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value of Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Available to Common Stockholders, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OperatingExpensesBeforeGainLossOnSaleOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating Expenses Before Gain Loss On Sale Of Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OperatingExpensesBeforeGainLossOnSaleOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses Before Gain Loss On Sale Of Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_OperatingExpensesBeforeGainLossOnSaleOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding borrowings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Line of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DefinityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">DEFINITY [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DefinityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">DEFINITY [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DefinityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">DEFINITY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Deferred Tax Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">% of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt and Lease Obligation, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: current portion of long-term debt and other borrowings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Investing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development Services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development Services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development Services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments and Hedging Activities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program, Remaining Authorized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock remain available for repurchase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money market funds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NoncashItemstoReconcileNetIncomeLosstoCashProvidedbyUsedinOperatingActivitiesDeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities, Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NoncashItemstoReconcileNetIncomeLosstoCashProvidedbyUsedinOperatingActivitiesDeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities, Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_NoncashItemstoReconcileNetIncomeLosstoCashProvidedbyUsedinOperatingActivitiesDeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationsRemediationCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Retirement Obligations, Remediation costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationsRemediationCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset retirement obligations, remediation costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AssetRetirementObligationsRemediationCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remediation costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities, excluding impact of acquisitions:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionSharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionSharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre existing debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Separately Recognized Transaction, Acquisition-Related Cost, Expensed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Property, Plant, and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFivePerecentageConvertibleSeniorNotesDueDecemberTwoThousandTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2.625% Convertible Senior Notes due December 2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFivePerecentageConvertibleSeniorNotesDueDecemberTwoThousandTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Point Six Two Five Perecentage Convertible Senior Notes due December Two Thousand Twenty Seven [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoPointSixTwoFivePerecentageConvertibleSeniorNotesDueDecemberTwoThousandTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two point six two five perecentage convertible senior notes due December two thousand twenty seven.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-In Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesAndLoansReceivableNetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term notes receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesAndLoansReceivableNetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financing Receivable, after Allowance for Credit Loss, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesAndLoansReceivableNetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Financing Receivable, after Allowance for Credit Loss, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchase program, authorized amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program, Authorized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Finite-Lived [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationCommissionExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disposal Group, Including Discontinued Operation, Commission Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationCommissionExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group, Including Discontinued Operation, Commission Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DisposalGroupIncludingDiscontinuedOperationCommissionExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commission expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CurrentlyMarketedProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Currently Marketed Product</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility, unused capacity, commitment fee percentage</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantCompliancePercentageOfAdditionalInterestUponNoncompliance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, Covenant Compliance, Percentage Of Additional Interest Upon Noncompliance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantCompliancePercentageOfAdditionalInterestUponNoncompliance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Covenant Compliance, Percentage Of Additional Interest Upon Noncompliance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DebtInstrumentCovenantCompliancePercentageOfAdditionalInterestUponNoncompliance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, covenant percentage of additional interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoThousandTwentyFiveSharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Five Share Purchase Program [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_UnsecuredPromissoryNoteReceivableStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unsecured Promissory Note Receivable Stated Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_UnsecuredPromissoryNoteReceivableStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of annual interest rate</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortizable, Accumulated Amortization</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentToInvestmentInEquitySecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment to investment in equity securities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentToInvestmentInEquitySecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase amount in investment in equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentsForAssetAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments For Asset Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_PaymentsForAssetAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments For Asset Acquisitions</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredOvernightFinancingRateSofrMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Secured Overnight Financing Rate (SOFR) [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodSharesOptionsExercisesDuringPeriodandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period, Shares, Options Exercises During Period and Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodSharesOptionsExercisesDuringPeriodandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Options Exercises During Period and Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_StockIssuedDuringPeriodSharesOptionsExercisesDuringPeriodandEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option exercises and employee stock plan purchases (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBoardFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Board Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBoardFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Board Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBoardFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of board fees</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Estimated Aggregate Amortization Expense Related to Intangible Assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment, Tax Withholding, Share-Based Payment Arrangement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_TwoThousandTwentyThreeEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty three employee stock purchase plan.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsExpensesAndLossesRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of transaction expenses</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Other Nonoperating Income (Expense) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Other Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BussinessCombinationNonrecurringPostCombinationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bussiness Combination Nonrecurring Post Combination Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BussinessCombinationNonrecurringPostCombinationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bussiness combination nonrecurring post combination expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_BussinessCombinationNonrecurringPostCombinationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nonrecurring post combination expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of common stock, including excise tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Repurchase of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchase of common stock, including excise tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration by Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration by Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Company's Contingent Consideration Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsidiary, Ownership Percentage, Noncontrolling Owner</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsidiary, ownership percentage, noncontrolling owner</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisposalGroupClassificationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Classification [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Income and Other Expense Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_WeightedAverageMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_WeightedAverageMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalPurchaseOfSharesInInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Purchase of Shares in Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalPurchaseOfSharesInInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional purchase of shares in investment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AdditionalPurchaseOfSharesInInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Purchase (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted income per common share (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Option, Quantitative Disclosures [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Option, Quantitative Disclosures [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AstraZenecaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AstraZeneca [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AstraZenecaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">AstraZeneca</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AstraZenecaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">AstraZeneca</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Liabilities Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicensingAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Licensing Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicensingAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Licenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument face amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility, maximum borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LicenseandRoyaltyRevenuesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and Royalty Revenues [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LicenseandRoyaltyRevenuesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License and Royalty Revenues [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_LicenseandRoyaltyRevenuesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and royalty revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashAfterJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash After January 1, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashAfterJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash after January 1, 2029.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_CashAfterJanuary12029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash After January 1, 2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Revenue by Major Customers, by Reporting Segments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Securities, FV-NI and without Readily Determinable Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment in equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note, Stock Split, Conversion Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_A1095CommercializationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">1095 Commercialization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_A1095CommercializationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">1095 Commercialization [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_A1095CommercializationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">1095 Commercialization [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposal Group Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disposal Group Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LetterOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Letter of Credit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LetterOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Letter of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Common Stock Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of common stock two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SaleOfCommonStockTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total property, plant&#160;and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset obtained in exchange for finance lease obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Finance Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of restricted stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Foreign Currency Translation, Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill, Foreign currency translation adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retained Earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EvergreenTheragnosticsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Evergreen Theragnostics [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EvergreenTheragnosticsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Evergreen Theragnostics</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EvergreenTheragnosticsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Evergreen Theragnostics.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt and Lease Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term debt and other borrowings, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtAndCapitalLeaseObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total long-term debt and other borrowings, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level&#160;1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnamortizedDebtIssuanceExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unamortized Debt Issuance Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnamortizedDebtIssuanceExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unamortized debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Developed Technology Rights [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Developed technology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Receivable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rest of world</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-US [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Indefinite-Lived Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Indefinite-Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MovementInValuationAllowancesAndReservesRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ReportableSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reportable Segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ReportableSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reportable Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_ReportableSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reportable Segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term income tax payable and other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility, current borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Current Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_SalesMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentAndCommercializationMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development and Commercialization Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentAndCommercializationMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development and commercialization milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DevelopmentAndCommercializationMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development and Commercialization Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LandMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Land [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LandMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Land</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price (in dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes on cash, cash equivalents and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Income, Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOther_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Compensation Arrangement with Individual, Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Arrangement with Individual, Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined contribution plan, contribution, vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Bonus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Arrangement with Individual, Maximum Percentage Of Bonus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of bonus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trademarks [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trademarks</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedRebatesAndDiscountsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Rebates and Discounts Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedRebatesAndDiscountsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued rebates and discounts current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_AccruedRebatesAndDiscountsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued rebates and discounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForCapitalImprovements_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Capital expenditures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EquityMethodInvestmentSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EquityMethodInvestmentSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity method investment shares outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lnth_EquityMethodInvestmentSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Method Investment Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Trading Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold trading days</link:label>
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  <xsd:element id="lnth_Scenario1Member" name="Scenario1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_BusinessCombinationConsideration" name="BusinessCombinationConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_PerspectiveTherapeuticsIncMember" name="PerspectiveTherapeuticsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_SHINEMember" name="SHINEMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_PaymentToDisposeABusinessRegardingRelatedPartyTransaction" name="PaymentToDisposeABusinessRegardingRelatedPartyTransaction" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_AssumedContingentConsiderationPiramalSPAMember" name="AssumedContingentConsiderationPiramalSPAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_MeasurementInputRevenueDiscountRateMember" name="MeasurementInputRevenueDiscountRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AssetRetirementObligationReclassificationToLiabilitiesHeldForSale" name="AssetRetirementObligationReclassificationToLiabilitiesHeldForSale" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_BussinessCombinationNonrecurringPostCombinationExpense" name="BussinessCombinationNonrecurringPostCombinationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_MeasurementInputRevenueVolatilityMember" name="MeasurementInputRevenueVolatilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_SellerNoteMember" name="SellerNoteMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_RevenueFromContractWithCustomerNumberOfProductCategories" name="RevenueFromContractWithCustomerNumberOfProductCategories" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_DebtInstrumentCovenantComplianceMinimumInterestCoverageRatio" name="DebtInstrumentCovenantComplianceMinimumInterestCoverageRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lnth_DebtInstrumentCovenantComplianceNumberOfFinancialCovenants" name="DebtInstrumentCovenantComplianceNumberOfFinancialCovenants" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_PYLARIFYMember" name="PYLARIFYMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AssetRetirementObligationAdjustmentToFairValue" name="AssetRetirementObligationAdjustmentToFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_StockRepurchasedDuringPeriodValueNet" name="StockRepurchasedDuringPeriodValueNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="lnth_SPECTBusinessMember" name="SPECTBusinessMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DebtInstrumentConvertibleConversionPremium" name="DebtInstrumentConvertibleConversionPremium" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_DebtInstrumentCovenantLeverageRatio" name="DebtInstrumentCovenantLeverageRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_SeriesE-1PreferredStockMember" name="SeriesE-1PreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_StrategicPartnershipsAndOtherMember" name="StrategicPartnershipsAndOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_PerspectiveCommonStockMember" name="PerspectiveCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_RadiopharmTheranosticsLimitedLicensedAssetsMember" name="RadiopharmTheranosticsLimitedLicensedAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_UnsecuredPromissoryNoteReceivableStatedPercentage" name="UnsecuredPromissoryNoteReceivableStatedPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lnth_DisposalGroupCarryingValueOfDeconsolidatedAssetsAndLiabilities" name="DisposalGroupCarryingValueOfDeconsolidatedAssetsAndLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_CashOnEarlierOfJanuary12029Member" name="CashOnEarlierOfJanuary12029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_FinancialAssuranceInFormOfSuretyBond" name="FinancialAssuranceInFormOfSuretyBond" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_SaleOfCommonStockTwoMember" name="SaleOfCommonStockTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_OtherNonoperatingIncomeExpenseMiscellaneous" name="OtherNonoperatingIncomeExpenseMiscellaneous" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_AssetRetirementObligationsRemediationCosts" name="AssetRetirementObligationsRemediationCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="lnth_TwoThousandTwentyThreeEmployeeStockPurchasePlanMember" name="TwoThousandTwentyThreeEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_MeilleurTechnologiesIncMember" name="MeilleurTechnologiesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="lnth_AdditionalPurchaseOfSharesInInvestment" name="AdditionalPurchaseOfSharesInInvestment" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lnth_ConversionAndCancellationAmountForInstallmentNote" name="ConversionAndCancellationAmountForInstallmentNote" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_NoteReceivableConversionPrice" name="NoteReceivableConversionPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lnth_InvestmentInEquitySecuritiesSharesOutstandingPercentage" name="InvestmentInEquitySecuritiesSharesOutstandingPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_Short-TermContingentConsideration" name="Short-TermContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_SaleOfCommonStockOneMember" name="SaleOfCommonStockOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AssetsLiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNetOfTransactionCosts" name="AssetsLiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNetOfTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="lnth_EBITDADiscountRateMember" name="EBITDADiscountRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_MachineryEquipmentAndFixturesMember" name="MachineryEquipmentAndFixturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DefinityMember" name="DefinityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_PrincipalOwedAmountRegardingImmaterialDerivativeRelatedToEarlyPotentialRepayment" name="PrincipalOwedAmountRegardingImmaterialDerivativeRelatedToEarlyPotentialRepayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
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  <xsd:element id="lnth_ReportableSegmentMember" name="ReportableSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="lnth_RelatedPartyTransactionCostRegardingTheSaleOfBusiness" name="RelatedPartyTransactionCostRegardingTheSaleOfBusiness" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_NetSalesTargetsForAzedraMember" name="NetSalesTargetsForAzedraMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="lnth_AdditionalRemainingPaymentsMember" name="AdditionalRemainingPaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_LantheusHoldingsIncMember" name="LantheusHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="lnth_AgreementWithPerspectiveTherapeuticsIncMember" name="AgreementWithPerspectiveTherapeuticsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_RevisionOfEstimatesDecommissioningCostsRelatedToAssetRetirementObligations" name="RevisionOfEstimatesDecommissioningCostsRelatedToAssetRetirementObligations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_A1095CommercializationMember" name="A1095CommercializationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DeferredCashPurchasePriceMember" name="DeferredCashPurchasePriceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets" name="BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
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  <xsd:element id="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseAsset" name="DisposalGroupIncludingDiscontinuedOperationRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_CollaborationPaymentsMember" name="CollaborationPaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DeferredCompensationArrangementWithIndividualMaximumPercentageOfBonus" name="DeferredCompensationArrangementWithIndividualMaximumPercentageOfBonus" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_SignificantAccountingPoliciesLineITems" name="SignificantAccountingPoliciesLineITems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AccruedRebatesAndDiscountsCurrent" name="AccruedRebatesAndDiscountsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_MeasurementInputProbabilityOfPaymentMember" name="MeasurementInputProbabilityOfPaymentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_ContingentConsiderationAssetsRelatedToSaleOfBusiness" name="ContingentConsiderationAssetsRelatedToSaleOfBusiness" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="lnth_PaymentOfWorkingCapitalSettlementInBusinessCombination" name="PaymentOfWorkingCapitalSettlementInBusinessCombination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_ProgenicsMember" name="ProgenicsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_OperatingExpensesBeforeGainLossOnSaleOfAssets" name="OperatingExpensesBeforeGainLossOnSaleOfAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_PaymentsForAssetAcquisitions" name="PaymentsForAssetAcquisitions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_StockIssuedDuringPeriodValueStockOptionsExercisedandEmployeeStockOwnershipPlan" name="StockIssuedDuringPeriodValueStockOptionsExercisedandEmployeeStockOwnershipPlan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_ChangeInFairValueOfContingentAssetsAndLiabilities" name="ChangeInFairValueOfContingentAssetsAndLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
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  <xsd:element id="lnth_A2625ConvertibleSeniorNotesDue2027Member" name="A2625ConvertibleSeniorNotesDue2027Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AstraZenecaMember" name="AstraZenecaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DevelopmentAndCommercializationMilestonesMember" name="DevelopmentAndCommercializationMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_ResearchRevenueMilestonesMember" name="ResearchRevenueMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_PromissoryNoteReceivable" name="PromissoryNoteReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_NeurologyMember" name="NeurologyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_LifeMolecularImagingLtdMember" name="LifeMolecularImagingLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="lnth_MaryAnneHeinoMember" name="MaryAnneHeinoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_SalesMilestoneMember" name="SalesMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_TwoThousandTwentyFiveSharePurchaseProgramMember" name="TwoThousandTwentyFiveSharePurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_SamuelR.LenoMember" name="SamuelR.LenoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DevelopmentServicesMember" name="DevelopmentServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_A2022FacilityCovenantsMember" name="A2022FacilityCovenantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_SaleOfCommonStockThreeMember" name="SaleOfCommonStockThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_TwoPointSixTwoFiveConvertibleSeniorNotesDueDecember2027Member" name="TwoPointSixTwoFiveConvertibleSeniorNotesDueDecember2027Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AssetAcquisitionsNumberOfAssetsAcquired" name="AssetAcquisitionsNumberOfAssetsAcquired" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lnth_LifeMolecularImagingIncMember" name="LifeMolecularImagingIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_RadiopharmTheranosticsLimitedMember" name="RadiopharmTheranosticsLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DebtInstrumentCovenantCompliancePercentageOfAdditionalInterestUponNoncompliance" name="DebtInstrumentCovenantCompliancePercentageOfAdditionalInterestUponNoncompliance" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lnth_SHINESPECTMember" name="SHINESPECTMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_AdditionalMilestonePaymentsMember" name="AdditionalMilestonePaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability" name="DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_LeaseModification" name="LeaseModification" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lnth_NonRefundableUpfrontPaymentToAdjustTheFutureRoyaltyObligations" name="NonRefundableUpfrontPaymentToAdjustTheFutureRoyaltyObligations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_TwoPointSixTwoFivePerecentageConvertibleSeniorNotesDueDecemberTwoThousandTwentySevenMember" name="TwoPointSixTwoFivePerecentageConvertibleSeniorNotesDueDecemberTwoThousandTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_UnsecuredPromissoryNoteReceivableAmount" name="UnsecuredPromissoryNoteReceivableAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lnth_NetContingentConsiderationReceivableMember" name="NetContingentConsiderationReceivableMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_CashAndCapitalStockMember" name="CashAndCapitalStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_NeuraceqMember" name="NeuraceqMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lnth_DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMaximumAmount" name="DecreaseInTheContingentRegulatoryAndDevelopmentMilestonesMaximumAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
