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        <link:definition>9955523 - Disclosure - NET INCOME (LOSS) PER COMMON SHARE (Tables)</link:definition>
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        <link:definition>9955530 - Disclosure - ASSETS AND LIABILITIES HELD FOR SALE (Details)</link:definition>
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  <xs:element id="pcrx_FinishedGoodsMember" abstract="true" name="FinishedGoodsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ComputerEquipmentAndSoftwareMember" abstract="true" name="ComputerEquipmentAndSoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_NumberOfLeases" abstract="false" name="NumberOfLeases" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AccruedSellingGeneralAndAdministrativeExpenses" abstract="false" name="AccruedSellingGeneralAndAdministrativeExpenses" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AccruedResearchAndDevelopmentExpenses" abstract="false" name="AccruedResearchAndDevelopmentExpenses" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AccruedProductionCost" abstract="false" name="AccruedProductionCost" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AccruedExpensesTable" abstract="true" name="AccruedExpensesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_AccruedExpensesLineItems" abstract="true" name="AccruedExpensesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_DisposalGroupIncludingDiscontinuedOperationProductLiabilitiesCurrent" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationProductLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_ConvertibleSeniorNotesDue2029Member" abstract="true" name="ConvertibleSeniorNotesDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_WellsFargoBankNationalAssociationCreditAgreementMember" abstract="true" name="WellsFargoBankNationalAssociationCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_TermLoanAFacilityDueMarch2028Member" abstract="true" name="TermLoanAFacilityDueMarch2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ConvertibleSeniorNotesDue2025Member" abstract="true" name="ConvertibleSeniorNotesDue2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DebtInstrumentConvertibleTermsOfConversionAxis" abstract="true" name="DebtInstrumentConvertibleTermsOfConversionAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_DebtInstrumentConvertibleTermsOfConversionDomain" abstract="true" name="DebtInstrumentConvertibleTermsOfConversionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DebtConversionTermsOneMember" abstract="true" name="DebtConversionTermsOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DebtConversionTermsTwoMember" abstract="true" name="DebtConversionTermsTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DebtConversionTermsThreeMember" abstract="true" name="DebtConversionTermsThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_CappedCallMember" abstract="true" name="CappedCallMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DebtInstrumentMarketPrice" abstract="false" name="DebtInstrumentMarketPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pcrx_DebtInstrumentRepurchasedInConversionFaceAmount" abstract="false" name="DebtInstrumentRepurchasedInConversionFaceAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_DebtInstrumentConvertibleThresholdPercentageOfStockTradingPrice" abstract="false" name="DebtInstrumentConvertibleThresholdPercentageOfStockTradingPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_SettlementPeriodConvertibleDebtConversionRequest" abstract="false" name="SettlementPeriodConvertibleDebtConversionRequest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_DebtInstrumentConversionObligationPremiumOnCommonStock" abstract="false" name="DebtInstrumentConversionObligationPremiumOnCommonStock" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_DebtInstrumentConvertibleRedemptionTradingDaysFromMaturity" abstract="false" name="DebtInstrumentConvertibleRedemptionTradingDaysFromMaturity" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_DerivativeCappedCallPrice" abstract="false" name="DerivativeCappedCallPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="pcrx_DerivativePremiumPercentage" abstract="false" name="DerivativePremiumPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_AdjustmentsToAdditionalPaidInCapitalPurchaseOfCappedCallsBeforeTax" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalPurchaseOfCappedCallsBeforeTax" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AdjustmentsToAdditionalPaidInCapitalPurchaseOfCappedCallsTax" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalPurchaseOfCappedCallsTax" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_DebtInstrumentCovenantIncrementalDebtMaximum" abstract="false" name="DebtInstrumentCovenantIncrementalDebtMaximum" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_DebtInstrumentCovenantIncrementalDebtMaximumPercent" abstract="false" name="DebtInstrumentCovenantIncrementalDebtMaximumPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_DebtInstrumentDiscountRate" abstract="false" name="DebtInstrumentDiscountRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_ConvertibleNotesReceivableMember" abstract="true" name="ConvertibleNotesReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_GQBioAcquisitionMember" abstract="true" name="GQBioAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetImpairments" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetImpairments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_EquityInvestmentAndConvertibleNoteReceivableMember" abstract="true" name="EquityInvestmentAndConvertibleNoteReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ContingentConsiderationMember" abstract="true" name="ContingentConsiderationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ConvertibleNoteReceivableMember" abstract="true" name="ConvertibleNoteReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_FlexionAcquisitionMember" abstract="true" name="FlexionAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_MajorCustomerOneMember" abstract="true" name="MajorCustomerOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_MajorCustomerTwoMember" abstract="true" name="MajorCustomerTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_MajorCustomerThreeMember" abstract="true" name="MajorCustomerThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ContingentConsiderationPaymentTerm" abstract="false" name="ContingentConsiderationPaymentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_NumberOfMajorCustomers" abstract="false" name="NumberOfMajorCustomers" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_MeasurementInputExpectedMilestonePaymentMember" abstract="true" name="MeasurementInputExpectedMilestonePaymentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ScheduleOfShortTermAndNoncurrentAvailableForSaleInvestmentsTable" abstract="true" name="ScheduleOfShortTermAndNoncurrentAvailableForSaleInvestmentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_InvestmentCategorizationAxis" abstract="true" name="InvestmentCategorizationAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_InvestmentCategorizationDomain" abstract="true" name="InvestmentCategorizationDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ShareRepurchaseProgramBrokerFees" abstract="false" name="ShareRepurchaseProgramBrokerFees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_InducementPlan2014Member" abstract="true" name="InducementPlan2014Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPurchasePeriods" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPurchasePeriods" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_RestrictedStockUnitsAndPerformanceStockUnitsMember" abstract="true" name="RestrictedStockUnitsAndPerformanceStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_EarningsPerShareBasicAndDilutedEPSAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedEPSAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_DeferredTaxAssetsTaxCreditCarryforwardsResearchDeductionYearOne" abstract="false" name="DeferredTaxAssetsTaxCreditCarryforwardsResearchDeductionYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_DeferredTaxAssetsTaxCreditCarryforwardsResearchDeductionYearTwo" abstract="false" name="DeferredTaxAssetsTaxCreditCarryforwardsResearchDeductionYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_DisposalGroupIncludingDiscontinuedOperationDivestitureRelatedExpenses" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationDivestitureRelatedExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_MyoScienceMilestoneLitigationMember" abstract="true" name="MyoScienceMilestoneLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_ResearchDevelopmentFoundationMember" abstract="true" name="ResearchDevelopmentFoundationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_LGChemPartnershipAgreementMember" abstract="true" name="LGChemPartnershipAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_JohnsonJohnsonMedTechMember" abstract="true" name="JohnsonJohnsonMedTechMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_GeneQuineMember" abstract="true" name="GeneQuineMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_BaylorCollegeOfMedicineBaylorMember" abstract="true" name="BaylorCollegeOfMedicineBaylorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_AchievementOfMilestoneAxis" abstract="true" name="AchievementOfMilestoneAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="pcrx_AchievementOfMilestoneDomain" abstract="true" name="AchievementOfMilestoneDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_AchievementOfDevelopmentAndRegulatoryMilestonesMember" abstract="true" name="AchievementOfDevelopmentAndRegulatoryMilestonesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_InitiationOfAPhase2ClinicalTrialMember" abstract="true" name="InitiationOfAPhase2ClinicalTrialMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_DevelopmentAndGlobalRegulatoryApprovalMilestonePaymentsMember" abstract="true" name="DevelopmentAndGlobalRegulatoryApprovalMilestonePaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_FlexionTherapeuticsIncMember" abstract="true" name="FlexionTherapeuticsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_LitigationSettlementVolumeLimitedIncreasePeriod" abstract="false" name="LitigationSettlementVolumeLimitedIncreasePeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_LitigationSettlementVolumeLimitedNumberOfModerateIncreasePeriods" abstract="false" name="LitigationSettlementVolumeLimitedNumberOfModerateIncreasePeriods" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_LitigationSettlementVolumeLimitedMaximumPercentagePeriod" abstract="false" name="LitigationSettlementVolumeLimitedMaximumPercentagePeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_NumberOfParagraphIVCertifications" abstract="false" name="NumberOfParagraphIVCertifications" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_NumberOfGenericDrugManufacturers" abstract="false" name="NumberOfGenericDrugManufacturers" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pcrx_LitigationSettlementAmountExpectedToBeAwardedFromOtherParty" abstract="false" name="LitigationSettlementAmountExpectedToBeAwardedFromOtherParty" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_ContractualObligationMinimumMonthlyCommissionDuration" abstract="false" name="ContractualObligationMinimumMonthlyCommissionDuration" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_ContractualObligationMutualTerminationRightsTerm" abstract="false" name="ContractualObligationMutualTerminationRightsTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_CollaborativeArrangementMilestonePaymentsToBeReceivedMaximum" abstract="false" name="CollaborativeArrangementMilestonePaymentsToBeReceivedMaximum" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_RevenueFromContractWithCustomerMilestonePaymentsMaximum" abstract="false" name="RevenueFromContractWithCustomerMilestonePaymentsMaximum" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_PercentOfLongLivedAssets" abstract="false" name="PercentOfLongLivedAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pcrx_CostOfGoodsSoldAdjusted" abstract="false" name="CostOfGoodsSoldAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_ResearchAndDevelopmentAdjusted" abstract="false" name="ResearchAndDevelopmentAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_SellingAndMarketingAdjusted" abstract="false" name="SellingAndMarketingAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_SellingGeneralAndAdministrativeAdjusted" abstract="false" name="SellingGeneralAndAdministrativeAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_AcquisitionRelatedCostAndDivestitureRelatedExpense" abstract="false" name="AcquisitionRelatedCostAndDivestitureRelatedExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pcrx_BusinessCombinationLiabilitiesArisingFromContingenciesPeriodOfRecognized" abstract="false" name="BusinessCombinationLiabilitiesArisingFromContingenciesPeriodOfRecognized" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pcrx_BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearOne" abstract="false" name="BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearOne" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearTwo" abstract="false" name="BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearTwo" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pcrx_BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearThree" abstract="false" name="BusinessCombinationLiabilitiesArisingFromContingenciesPercentYearThree" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
