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<!-- Creation Date :2022-02-28T21:41:22.7276+00:00 -->
<!-- Copyright (c) 2022 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="amrn_ContractWithCustomerLiabilityRevenueRecognizedExcludingPerformanceObligationSatisfiedInPreviousPeriod" name="ContractWithCustomerLiabilityRevenueRecognizedExcludingPerformanceObligationSatisfiedInPreviousPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_ConversionPricePerShare" name="ConversionPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_CoPromotionTailPaymentsPayable" name="CoPromotionTailPaymentsPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_CreditsPaymentsMadeForPriorPeriodSales" name="CreditsPaymentsMadeForPriorPeriodSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_DeferredRevenueRecognitionPeriod" name="DeferredRevenueRecognitionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_DeferredTaxAssetLeaseLiability" name="DeferredTaxAssetLeaseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_DeferredTaxAssetsOperatingLossCarryforwardsChangeInAmount" name="DeferredTaxAssetsOperatingLossCarryforwardsChangeInAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_DeferredTaxLiabilitiesDepreciationAndAmortization" name="DeferredTaxLiabilitiesDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_DeferredTaxLiabilitiesSubjectToExpiration" name="DeferredTaxLiabilitiesSubjectToExpiration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_DeferredTaxLiabilityLeaseAsset" name="DeferredTaxLiabilityLeaseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_DepreciationAndAmortizationExcludingAmortizationOfIntangibleAssets" name="DepreciationAndAmortizationExcludingAmortizationOfIntangibleAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_DisposalPurchaseOfFurnitureFixturesAndEquipment" name="DisposalPurchaseOfFurnitureFixturesAndEquipment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_EligibleRegulatoryMilestoneEventsToBeReceived" name="EligibleRegulatoryMilestoneEventsToBeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_EligibleSalesBasedMilestoneEventsToBeReceived" name="EligibleSalesBasedMilestoneEventsToBeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_EmployeeServiceShareBasedCompensationTaxBenefitDeficiencyRealizedFromExerciseOfStockOptions" name="EmployeeServiceShareBasedCompensationTaxBenefitDeficiencyRealizedFromExerciseOfStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_EquityOfferingCosts" name="EquityOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_HeldToMaturitySecuritiesContinuousUnrealizedGainLossPositionFairValue" name="HeldToMaturitySecuritiesContinuousUnrealizedGainLossPositionFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxRateReconciliationCumulativeTranslationAdjustmentAmount" name="IncomeTaxRateReconciliationCumulativeTranslationAdjustmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationDisqualifyingDispositionWindfall" name="IncomeTaxReconciliationDisqualifyingDispositionWindfall" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationLiquidation" name="IncomeTaxReconciliationLiquidation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationLongTermDebtRoyaltyBearingInstrument" name="IncomeTaxReconciliationLongTermDebtRoyaltyBearingInstrument" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationNetOperatingLossCarryback" name="IncomeTaxReconciliationNetOperatingLossCarryback" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationTaxReserve" name="IncomeTaxReconciliationTaxReserve" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_IncomeTaxReconciliationWindfallTaxBenefitShortfall" name="IncomeTaxReconciliationWindfallTaxBenefitShortfall" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_InitialRecognitionOfOperatingLeaseRightOfUseAsset" name="InitialRecognitionOfOperatingLeaseRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_InventoryCurrentAndNonCurrent" name="InventoryCurrentAndNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_LesseeOperatingLeaseLiabilityPaymentsDueYearSixAndThereafter" name="LesseeOperatingLeaseLiabilityPaymentsDueYearSixAndThereafter" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_MaximumCoPromotionTailPaymentsReceivePeriod" name="MaximumCoPromotionTailPaymentsReceivePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_MilestonePaymentAchieved" name="MilestonePaymentAchieved" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_NetIncomeLossAvailableToCommonStockholdersBasicAndDiluted" name="NetIncomeLossAvailableToCommonStockholdersBasicAndDiluted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_NetOperatingLossCarrybackPeriod" name="NetOperatingLossCarrybackPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_NonCashOrPartNonCashMilestonePayment" name="NonCashOrPartNonCashMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_NonRefundableAndNonCreditableUpfrontPayment" name="NonRefundableAndNonCreditableUpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_NonrefundableMilestonePaymentReceived" name="NonrefundableMilestonePaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_NonrefundableMilestonePaymentReceiveds" name="NonrefundableMilestonePaymentReceiveds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_NonRefundableUpfrontPaymentsReceived" name="NonRefundableUpfrontPaymentsReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_NonRefundableUpfrontPaymentsReceivedPeriod" name="NonRefundableUpfrontPaymentsReceivedPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_NumberOfCustomers" name="NumberOfCustomers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_NumberOfRegulatoryMilestoneEventsIndications" name="NumberOfRegulatoryMilestoneEventsIndications" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_NumberOfRenewalOptions" name="NumberOfRenewalOptions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_NumberOfSalesRepresentatives" name="NumberOfSalesRepresentatives" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_OperatingLeaseChangeInWeightedAverageDiscountRatePercent" name="OperatingLeaseChangeInWeightedAverageDiscountRatePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_OperatingLeaseCommencementDate" name="OperatingLeaseCommencementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_PaymentOfMilestones" name="PaymentOfMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_PercentageOfGrossMarginPayableForPromotionAgreement" name="PercentageOfGrossMarginPayableForPromotionAgreement" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_PercentageOfOutstandingCommonSharesAndPreferredSharesOnFullyDilutedBasis" name="PercentageOfOutstandingCommonSharesAndPreferredSharesOnFullyDilutedBasis" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_PotentialMilestonePaymentUponMarketingApproval" name="PotentialMilestonePaymentUponMarketingApproval" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_PreferredStockEquivalentOrdinarySharesUponFutureConversionOutstanding" name="PreferredStockEquivalentOrdinarySharesUponFutureConversionOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ProceedsFromStockOptionsExercisedGross" name="ProceedsFromStockOptionsExercisedGross" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_ProductApprovalYearAndMonth" name="ProductApprovalYearAndMonth" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ProductExpirationPeriodUponConversionIntoCapsuleForm" name="ProductExpirationPeriodUponConversionIntoCapsuleForm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ProductLaunchYearAndMonth" name="ProductLaunchYearAndMonth" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ProvisionRelatedToPriorPeriodSales" name="ProvisionRelatedToPriorPeriodSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_RestructuringCostsIncurred" name="RestructuringCostsIncurred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="amrn_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumFMVOfSharesPurchasedPerEmployeeCalendarYr" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumFMVOfSharesPurchasedPerEmployeeCalendarYr" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalGrantsInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalGrantsInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ShortTermLeasePeriod" name="ShortTermLeasePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_StatutoryTaxRate" name="StatutoryTaxRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_StockIssuedDuringPeriodSharesMilestonePayment" name="StockIssuedDuringPeriodSharesMilestonePayment" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_StockIssuedDuringPeriodValueMilestonePayment" name="StockIssuedDuringPeriodValueMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_TaxCreditCarryforwardExpirationYear" name="TaxCreditCarryforwardExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_ValuationAllowancesAndReservesForeignCurrencyTranslation" name="ValuationAllowancesAndReservesForeignCurrencyTranslation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_ValuationAllowancesProvisionsAndReservesBalanceNet" name="ValuationAllowancesProvisionsAndReservesBalanceNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="amrn_BusinessDevelopmentDomain" name="BusinessDevelopmentDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LocationsDomain" name="LocationsDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_TaxesByNatureDomain" name="TaxesByNatureDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CommitmentsAndContingenciesDisclosureLineItems" name="CommitmentsAndContingenciesDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CoPromotionAgreementLineItems" name="CoPromotionAgreementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_DebtDisclosureLineItems" name="DebtDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_DocumentAndEntityInformationLineItems" name="DocumentAndEntityInformationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_IncomeTaxLineItems" name="IncomeTaxLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LicenseAndCollaborationAgreementsLineItems" name="LicenseAndCollaborationAgreementsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StockholdersEquityNoteLineItems" name="StockholdersEquityNoteLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_AgencySecurityMember" name="AgencySecurityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_AllowanceForDoubtfulAccountMember" name="AllowanceForDoubtfulAccountMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_AllowanceForEstimatedChargebacksMember" name="AllowanceForEstimatedChargebacksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_AmarinPharmaceuticalsIrelandLimitedMember" name="AmarinPharmaceuticalsIrelandLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_AmericanDepositaryShareMember" name="AmericanDepositaryShareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_BiologixMember" name="BiologixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_BiopharmaceuticalMember" name="BiopharmaceuticalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_BridgewaterMember" name="BridgewaterMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CARESActMember" name="CARESActMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ChargesCashMember" name="ChargesCashMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ClinicalTrialApplicationMember" name="ClinicalTrialApplicationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CoPromotionAgreementMember" name="CoPromotionAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CPPIBMember" name="CPPIBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CustomerAMember" name="CustomerAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CustomerBMember" name="CustomerBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CustomerCMember" name="CustomerCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_DomesticCountryRepublicOfIrelandUnitedKingdomAndIsraelMember" name="DomesticCountryRepublicOfIrelandUnitedKingdomAndIsraelMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_EddingMember" name="EddingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_EmployeesMember" name="EmployeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_FederalMember" name="FederalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_FoodAndDrugAdministrationMember" name="FoodAndDrugAdministrationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_FurtherIndicationForAMROneZeroOneMember" name="FurtherIndicationForAMROneZeroOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_GoToMarketStrategyMember" name="GoToMarketStrategyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_HealthCanadaMember" name="HealthCanadaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_HLSTherapeuticsIncorporationMember" name="HLSTherapeuticsIncorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_InLicensesAgreementMember" name="InLicensesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_IrelandAndUnitedKingdomMember" name="IrelandAndUnitedKingdomMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_KowaPharmaceuticalsAmericaIncorporationMember" name="KowaPharmaceuticalsAmericaIncorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LaxdaleMilestoneSharesMember" name="LaxdaleMilestoneSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LicensingAndRoyaltyMember" name="LicensingAndRoyaltyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LongTermInvestmentsMember" name="LongTermInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_MarineMember" name="MarineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_MarketingApprovalInEuropeMember" name="MarketingApprovalInEuropeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_MochidaPharmaceuticalCoLtdMember" name="MochidaPharmaceuticalCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_MoneyMarketInstrumentsMember" name="MoneyMarketInstrumentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_NonCashMember" name="NonCashMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_NonTradingActivityMember" name="NonTradingActivityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OfficeSpaceMember" name="OfficeSpaceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OrdinarySharesBasisMember" name="OrdinarySharesBasisMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OrdinarySharesMember" name="OrdinarySharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OtherCountryMember" name="OtherCountryMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OtherIncentiveProgramsMember" name="OtherIncentiveProgramsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_OutLicensesAgreementMember" name="OutLicensesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_PerformanceBasedRestrictedStockUnitsMember" name="PerformanceBasedRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_PotentialMarketingApprovalOneMember" name="PotentialMarketingApprovalOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_PotentialMarketingApprovalTwoMember" name="PotentialMarketingApprovalTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_PreferredSharesBasisMember" name="PreferredSharesBasisMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ProductReturnsMember" name="ProductReturnsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_RebatesChargebacksAndDiscountsMember" name="RebatesChargebacksAndDiscountsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ReduceItMember" name="ReduceItMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_RepoSecuritiesMember" name="RepoSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_RoyaltyBearingDebtMember" name="RoyaltyBearingDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StateMember" name="StateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StockIncentivePlanTwentyTwentyAndStockIncentivePlanTwentyElevenMember" name="StockIncentivePlanTwentyTwentyAndStockIncentivePlanTwentyElevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StockIncentivePlanTwentyTwentyAndTwentyElevenMember" name="StockIncentivePlanTwentyTwentyAndTwentyElevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StockIncentivePlanTwentyTwentyMember" name="StockIncentivePlanTwentyTwentyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_TradingActivityMember" name="TradingActivityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_TwoThousandAndSeventeenEmployeeStockPurchasePlanMember" name="TwoThousandAndSeventeenEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_VASCEPAHalfGramMember" name="VASCEPAHalfGramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_VascepaMember" name="VascepaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_VASCEPAOneGramMember" name="VASCEPAOneGramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ZugMember" name="ZugMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_ConcentrationOfSuppliersPolicyTextBlock" name="ConcentrationOfSuppliersPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_DistributionCostsRelatedToShippingProductPolicyTextBlock" name="DistributionCostsRelatedToShippingProductPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_UseOfForecastedFinancialInformationInAccountingEstimatesPolicyTextBlock" name="UseOfForecastedFinancialInformationInAccountingEstimatesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_CommitmentsAndContingenciesDisclosureTable" name="CommitmentsAndContingenciesDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_CoPromotionAgreementTable" name="CoPromotionAgreementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_DebtDisclosureTable" name="DebtDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_DocumentAndEntityInformationTable" name="DocumentAndEntityInformationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_IncomeTaxTable" name="IncomeTaxTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_LicenseAndCollaborationAgreementsTable" name="LicenseAndCollaborationAgreementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_StockholdersEquityNoteTable" name="StockholdersEquityNoteTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="amrn_SummaryOfNetProductRevenueValuationAllowancesTableTextBlock" name="SummaryOfNetProductRevenueValuationAllowancesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_AccruedExpensesAndOtherLiabilitiesDisclosureTextBlock" name="AccruedExpensesAndOtherLiabilitiesDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_CoPromotionAgreementDisclosureTextBlock" name="CoPromotionAgreementDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="amrn_SummaryOfProductApprovalTableTextBlock" name="SummaryOfProductApprovalTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
