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  <xs:element id="mck_SeniorUnsecuredCreditFacilityThe2022CreditFacilityMember" abstract="true" name="SeniorUnsecuredCreditFacilityThe2022CreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_SeniorUnsecuredCreditFacility364DayCreditFacilityMember" abstract="true" name="SeniorUnsecuredCreditFacility364DayCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_SeniorUnsecuredCreditFacilityThe2026CreditFacilityMember" abstract="true" name="SeniorUnsecuredCreditFacilityThe2026CreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_DerivativeNotionalAmountTerminated" abstract="false" name="DerivativeNotionalAmountTerminated" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_DerivativeNotionalAmountEnteredIntoDuringPeriod" abstract="false" name="DerivativeNotionalAmountEnteredIntoDuringPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_InterestRateSwapLocksMember" abstract="true" name="InterestRateSwapLocksMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_EquityAndDebtSecurities" abstract="false" name="EquityAndDebtSecurities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_NationalPrescriptionOpiateLitigationMember" abstract="true" name="NationalPrescriptionOpiateLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_StateOfAlabamaAndSubdivisionsMember" abstract="true" name="StateOfAlabamaAndSubdivisionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_WestVirginiaSubdivisionsMember" abstract="true" name="WestVirginiaSubdivisionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_NativeAmericanTribesOtherThanCherokeeNationMember" abstract="true" name="NativeAmericanTribesOtherThanCherokeeNationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_IndividualClaimantMember" abstract="true" name="IndividualClaimantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_CompensatoryDamagesMember" abstract="true" name="CompensatoryDamagesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_MonetaryAbatementMember" abstract="true" name="MonetaryAbatementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_LossContingencyNumberOfOtherDefendants" abstract="false" name="LossContingencyNumberOfOtherDefendants" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mck_LossContingencyNumberOfStates" abstract="false" name="LossContingencyNumberOfStates" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mck_LossContingencyNumberOfCasesDismissed" abstract="false" name="LossContingencyNumberOfCasesDismissed" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mck_LitigationSettlementAwardAmountToBeUsedByStateAndLocalGovernmentPercentageOfTotalSettlementToBeUsedToRemediateDamages" abstract="false" name="LitigationSettlementAwardAmountToBeUsedByStateAndLocalGovernmentPercentageOfTotalSettlementToBeUsedToRemediateDamages" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mck_LossContingencyClaimsSettledNumberOfJurisdictionsNotParticipatingInSettlement" abstract="false" name="LossContingencyClaimsSettledNumberOfJurisdictionsNotParticipatingInSettlement" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mck_LitigationSettlementAmountAwardedToOtherPartyPercentageOfTotalSettlementToBeUsedToRemediateDamages" abstract="false" name="LitigationSettlementAmountAwardedToOtherPartyPercentageOfTotalSettlementToBeUsedToRemediateDamages" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="mck_SharesRepurchasedMember" abstract="true" name="SharesRepurchasedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_CommonStockVotingRightsNumberofVotesPerCommonShare" abstract="false" name="CommonStockVotingRightsNumberofVotesPerCommonShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mck_ExciseTaxAccrual" abstract="false" name="ExciseTaxAccrual" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_ExciseTaxPayment" abstract="false" name="ExciseTaxPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_AcceleratedShareRepurchaseMarch2026Member" abstract="true" name="AcceleratedShareRepurchaseMarch2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_AcceleratedShareRepurchaseMay2026Member" abstract="true" name="AcceleratedShareRepurchaseMay2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_OpenMarketTransactionsMember" abstract="true" name="OpenMarketTransactionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_ShareRepurchasesApproximateDollarValueOfSharesThatMayYetBePurchasedUnderTheProgramsRollForward" abstract="true" name="ShareRepurchasesApproximateDollarValueOfSharesThatMayYetBePurchasedUnderTheProgramsRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="mck_ShareRepurchaseProgramAdditionalNumberOfSharesAuthorized" abstract="false" name="ShareRepurchaseProgramAdditionalNumberOfSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mck_AOCIAccumulatedGainLossNetInvestmentHedgesIncludingNoncontrollingInterestMember" abstract="true" name="AOCIAccumulatedGainLossNetInvestmentHedgesIncludingNoncontrollingInterestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mck_GrossProfitNetOfExpensesIncludingOtherIncome" abstract="false" name="GrossProfitNetOfExpensesIncludingOtherIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_CorporateOperatingExpenseAndOtherIncomeNet" abstract="false" name="CorporateOperatingExpenseAndOtherIncomeNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_RevenueDerivedFromServicesPercentage" abstract="false" name="RevenueDerivedFromServicesPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mck_BusinessSeparationCosts" abstract="false" name="BusinessSeparationCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mck_PropertyPlantAndEquipmentIncludingNetCapitalizedSoftware" abstract="false" name="PropertyPlantAndEquipmentIncludingNetCapitalizedSoftware" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
