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  <xsd:element name="DisclosureOfDetailedInformationAboutCashAndCashEquivalentsExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutCashAndCashEquivalentsExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutEvolutionOfShareCapitalAndSharePremiumExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutEvolutionOfShareCapitalAndSharePremiumExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherComprehensiveIncomeReserveExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutOtherComprehensiveIncomeReserveExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfFinancialDebtExplanatory" id="nyxh_DisclosureOfFinancialDebtExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfRecoverableCashAdvancesExplanatory" id="nyxh_DisclosureOfRecoverableCashAdvancesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfFairValueOfRecoverableCashAdvancesExplanatory" id="nyxh_DisclosureOfFairValueOfRecoverableCashAdvancesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutTradePayablesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutTradePayablesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherPayablesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutOtherPayablesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutEmployeeBenefitsExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutEmployeeBenefitsExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutFinanceIncomeExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutFinanceIncomeExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutFinanceExpenseExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutFinanceExpenseExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutIncomeTaxExpensesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutIncomeTaxExpensesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutNumberOfSharesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutNumberOfSharesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutRemunerationOfKeyManagementExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutRemunerationOfKeyManagementExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutTransactionsWithRelatedPartiesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutTransactionsWithRelatedPartiesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutEarningsPerShareExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutEarningsPerShareExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ClassesOfEmployeeBenefitsExpenseLineItems" id="nyxh_ClassesOfEmployeeBenefitsExpenseLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfFinancialDebtAbstract" id="nyxh_DisclosureOfFinancialDebtAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EquitySettledShareBasedPaymentsAbstract" id="nyxh_EquitySettledShareBasedPaymentsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfFinancialDebtLineItems" id="nyxh_DisclosureOfFinancialDebtLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PurchasesOfGoodsAndServices" id="nyxh_PurchasesOfGoodsAndServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DevelopmentCostMember" id="nyxh_DevelopmentCostMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PatentsAndLicensesMember" id="nyxh_PatentsAndLicensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfFinancialDebtTable" id="nyxh_DisclosureOfFinancialDebtTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OtherComprehensiveIncomeReserveLineItems" id="nyxh_OtherComprehensiveIncomeReserveLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CostsOfGoodsSoldLineItems" id="nyxh_CostsOfGoodsSoldLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RecoverableCashAdvancesDiscountingImpact" id="nyxh_RecoverableCashAdvancesDiscountingImpact" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DocumentAndEntityInformationAbstract" id="nyxh_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncomeTaxesAbstract" id="nyxh_IncomeTaxesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SharePremiumBeforeDeductionOfTransactionCosts" id="nyxh_SharePremiumBeforeDeductionOfTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutInventoriesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutInventoriesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutCostOfGoodsSoldExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutCostOfGoodsSoldExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOperatingExpensesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutOperatingExpensesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherOperatingExpensesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutOtherOperatingExpensesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutResearchAndDevelopmentExpensesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutResearchAndDevelopmentExpensesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExpensesCategoriesAxis" id="nyxh_ExpensesCategoriesAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ExpensesCategoriesDomain" id="nyxh_ExpensesCategoriesDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RateImpactDomain" id="nyxh_RateImpactDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IfrsLegalEntityAxis" id="nyxh_IfrsLegalEntityAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IfrsEntityDomain" id="nyxh_IfrsEntityDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DeferredTaxAssetAndLiabilitiesAxis" id="nyxh_DeferredTaxAssetAndLiabilitiesAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DeferredTaxAssetAndLiabilitiesDomain" id="nyxh_DeferredTaxAssetAndLiabilitiesDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TotalOfShareMember" id="nyxh_TotalOfShareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CommonShareMember" id="nyxh_CommonShareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="VariationOfDiscountRateAxis" id="nyxh_VariationOfDiscountRateAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="VariationOfDiscountRateDomain" id="nyxh_VariationOfDiscountRateDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="VariationOfRevenueProjectionAxis" id="nyxh_VariationOfRevenueProjectionAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="VariationOfRevenueProjectionsDomain" id="nyxh_VariationOfRevenueProjectionsDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ExpenseCategoriesDomain" id="nyxh_ExpenseCategoriesDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Ifrs_BalanceSheetLocationAxis" id="nyxh_Ifrs_BalanceSheetLocationAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Ifrs_BalanceSheetLocationDomain" id="nyxh_Ifrs_BalanceSheetLocationDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ResearchAndDevelopmentExpensesMember" id="nyxh_ResearchAndDevelopmentExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockholdersEquityNoteStockSplitConversionRatio1" id="nyxh_StockholdersEquityNoteStockSplitConversionRatio1" type="xbrli:pureItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OperatingExpenseBenefits" id="nyxh_OperatingExpenseBenefits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NyxoahLtdMember" id="nyxh_NyxoahLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NyxoahPtyLtdMember" id="nyxh_NyxoahPtyLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NyxoahIncMember" id="nyxh_NyxoahIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementIssuedOnGranted" id="nyxh_ShareBasedPaymentArrangementIssuedOnGranted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DisclosureOfFairValueMeasurementAbstract" id="nyxh_DisclosureOfFairValueMeasurementAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FinancialIncomeAbstract" id="nyxh_FinancialIncomeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FinancialExpenseAbstract" id="nyxh_FinancialExpenseAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DisclosureOfInventoriesAbstract" id="nyxh_DisclosureOfInventoriesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PreferredSharesWereConvertedIntoCommonSharesAndSplitSharesAbstract" id="nyxh_PreferredSharesWereConvertedIntoCommonSharesAndSplitSharesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResultsOfOperationsAbstract" id="nyxh_ResultsOfOperationsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DisclosureOfResultsOfOperationsTextBlock" id="nyxh_DisclosureOfResultsOfOperationsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ManufacturingAndOutsourcedDevelopmentsExpense" id="nyxh_ManufacturingAndOutsourcedDevelopmentsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="QualityAssuranceRegulatory" id="nyxh_QualityAssuranceRegulatory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ForeignCurrencyForwardsMember" id="nyxh_ForeignCurrencyForwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DisclosureOfDetailedInformationAboutSellingGeneralAndAdministrativeExpensesTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutSellingGeneralAndAdministrativeExpensesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutChangesInHedgingInstrumentsTableTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutChangesInHedgingInstrumentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutFairValueHierarchyHedgingInstrumentTableTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutFairValueHierarchyHedgingInstrumentTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ResearchAndDevelopmentExpensesBeforeCapitalization" id="nyxh_ResearchAndDevelopmentExpensesBeforeCapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OtherOperatingIncomeExpenseInitialMeasurementAndReMeasurement" id="nyxh_OtherOperatingIncomeExpenseInitialMeasurementAndReMeasurement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OtherOperatingIncomeExpenseResearchAndDevelopmentIncentives" id="nyxh_OtherOperatingIncomeExpenseResearchAndDevelopmentIncentives" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OtherOperatingIncomeExpenseCapitalizationOfResearchAndDevelopmentIncentives" id="nyxh_OtherOperatingIncomeExpenseCapitalizationOfResearchAndDevelopmentIncentives" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OtherOperatingIncomeExpenseMiscellaneousIncomeExpense" id="nyxh_OtherOperatingIncomeExpenseMiscellaneousIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IfrsNumberOfReportableSegments" id="nyxh_IfrsNumberOfReportableSegments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="UnbilledReceivablesIncludedInTradeReceivables" id="nyxh_UnbilledReceivablesIncludedInTradeReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DisclosureOfGeneralInformationAbstract" id="nyxh_DisclosureOfGeneralInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DisclosureOfInformationAboutForeignCurrencySwapsTableTextBlock" id="nyxh_DisclosureOfInformationAboutForeignCurrencySwapsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsStockholdersEquityNoteStockSplitConversionRatio" id="nyxh_IfrsStockholdersEquityNoteStockSplitConversionRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsSaleOfStockAxis" id="nyxh_IfrsSaleOfStockAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsSaleOfStockDomain" id="nyxh_IfrsSaleOfStockDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SalePricePerShare" id="nyxh_SalePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LegalFeesExpense" id="nyxh_LegalFeesExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OtherOperatingIncomeExpenseAbstract" id="nyxh_OtherOperatingIncomeExpenseAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CurrentTaxLiabilitiesCurrentUncertainTaxPositions" id="nyxh_CurrentTaxLiabilitiesCurrentUncertainTaxPositions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="UsdTermDepositsMember" id="nyxh_UsdTermDepositsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ZeroPercentRevenueProjectionIncreaseMember" id="nyxh_ZeroPercentRevenueProjectionIncreaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TwentyFivePercentRevenueProjectionIncreaseMember" id="nyxh_TwentyFivePercentRevenueProjectionIncreaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TwentyFivePercentRevenueProjectionDecreaseMember" id="nyxh_TwentyFivePercentRevenueProjectionDecreaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CochlearLimitedMember" id="nyxh_CochlearLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="KevinRakinMember" id="nyxh_KevinRakinMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PierreGianelloMember" id="nyxh_PierreGianelloMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="JurgenHambrechtMember" id="nyxh_JurgenHambrechtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RitaMillsMember" id="nyxh_RitaMillsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GinyKirbyMember" id="nyxh_GinyKirbyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CarryingValueAndFairValueOfDerivativeFinancialAssetsAndLiabilities." id="nyxh_CarryingValueAndFairValueOfDerivativeFinancialAssetsAndLiabilities." type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NyxoahGmbhMember" id="nyxh_NyxoahGmbhMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UsTreasuryBillsMember" id="nyxh_UsTreasuryBillsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2021GrantSept172021Member" id="nyxh_ShareBasedPaymentArrangementsPlan2021GrantSept172021Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2021GrantOct272021Member" id="nyxh_ShareBasedPaymentArrangementsPlan2021GrantOct272021Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2021GrantFeb212022Member" id="nyxh_SharebasedPaymentArrangementsPlan2021GrantFeb212022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2021GrantMay142022Member" id="nyxh_SharebasedPaymentArrangementsPlan2021GrantMay142022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherLongTermReceivablesAbstract" id="nyxh_OtherLongTermReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherLongTermReceivablesTextBlock" id="nyxh_OtherLongTermReceivablesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfCustomersWithIndividualSales" id="nyxh_NumberOfCustomersWithIndividualSales" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="TaxIncentiveReceivable" id="nyxh_TaxIncentiveReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="InformationTechnologyExpenseSellingGeneralAndAdministrativeExpenses" id="nyxh_InformationTechnologyExpenseSellingGeneralAndAdministrativeExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IfrsClassOfWarrantsOrRightAxis" id="nyxh_IfrsClassOfWarrantsOrRightAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ClassOfWarrantsOrRightDomain" id="nyxh_ClassOfWarrantsOrRightDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LevelIAndIiiMember" id="nyxh_LevelIAndIiiMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdditionalTaxAccrualForUncertainPosition" id="nyxh_AdditionalTaxAccrualForUncertainPosition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeExpensesMemberMember" id="nyxh_SellingGeneralAndAdministrativeExpensesMemberMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ContractualRecoverableCashAdvances" id="nyxh_ContractualRecoverableCashAdvances" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SleepApneaDeviceMember" id="nyxh_SleepApneaDeviceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FirstArticlesMember" id="nyxh_FirstArticlesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ClinicalTrialsMember" id="nyxh_ClinicalTrialsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ActivationChipImprovementsMember" id="nyxh_ActivationChipImprovementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RecoverableCashAdvancesDiscountingImpactB.s" id="nyxh_RecoverableCashAdvancesDiscountingImpactB.s" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseThroughForfeitureShareBasedPayments." id="nyxh_IncreaseDecreaseThroughForfeitureShareBasedPayments." type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ConstructionAndLaboratoryEquipmentMember" id="nyxh_ConstructionAndLaboratoryEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2022GrantApr212024Member" id="nyxh_SharebasedPaymentArrangementsPlan2022GrantApr212024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2022GrantFeb012024Member" id="nyxh_SharebasedPaymentArrangementsPlan2022GrantFeb012024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RecoverableCashFixedReimbursed" id="nyxh_RecoverableCashFixedReimbursed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RecoverableCashVariableReimbursed" id="nyxh_RecoverableCashVariableReimbursed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FinancialAssetsWhichWouldNotGenerateExchangeGainOrLossMember" id="nyxh_FinancialAssetsWhichWouldNotGenerateExchangeGainOrLossMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncreaseDecreaseInTradePayables" id="nyxh_IncreaseDecreaseInTradePayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInIncomeTaxPayableOrReimbursedBySubsidiaries" id="nyxh_IncreaseDecreaseInIncomeTaxPayableOrReimbursedBySubsidiaries" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LoanFacilityWithEuropeanInvestmentBankMember" id="nyxh_LoanFacilityWithEuropeanInvestmentBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExpenseOperatingExpense" id="nyxh_ResearchAndDevelopmentExpenseOperatingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FirstTrancheMember" id="nyxh_FirstTrancheMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfReasonablyPossibleChangeInRiskAssumptionAxis" id="nyxh_PercentageOfReasonablyPossibleChangeInRiskAssumptionAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfReasonablyPossibleChangeInRiskAssumptionDomain" id="nyxh_PercentageOfReasonablyPossibleChangeInRiskAssumptionDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RecoverableCashAdvances.Member" id="nyxh_RecoverableCashAdvances.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TradeAndOtherPayablesMember" id="nyxh_TradeAndOtherPayablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherCurrentAssets.Member" id="nyxh_OtherCurrentAssets.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CashAndCashEquivalent.Member" id="nyxh_CashAndCashEquivalent.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FinancialAssets.Member" id="nyxh_FinancialAssets.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TermDeposits.Member" id="nyxh_TermDeposits.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfEquitySettledShareBasedIncentivePlans" id="nyxh_NumberOfEquitySettledShareBasedIncentivePlans" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedPaymentArrangementAllPlansMember" id="nyxh_ShareBasedPaymentArrangementAllPlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfWarrantsGranted" id="nyxh_NumberOfWarrantsGranted" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExercisePricePerWarrant" id="nyxh_ExercisePricePerWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="NumberOfWarrantsGrantedAndNotAccepted" id="nyxh_NumberOfWarrantsGrantedAndNotAccepted" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExpectedDividendAsPercentageOtherEquityInstruments" id="nyxh_ExpectedDividendAsPercentageOtherEquityInstruments" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DescriptionOfExpectedVolatilityOtherEquityInstrumentGranted" id="nyxh_DescriptionOfExpectedVolatilityOtherEquityInstrumentGranted" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DescriptionOfRiskFreeInterestRateOtherEquityInstrumentGranted." id="nyxh_DescriptionOfRiskFreeInterestRateOtherEquityInstrumentGranted." type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DescriptionOfOptionLifeOtherEquityInstrumentGranted" id="nyxh_DescriptionOfOptionLifeOtherEquityInstrumentGranted" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExercisePriceOtherEquityInstrumentGranted" id="nyxh_ExercisePriceOtherEquityInstrumentGranted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="WeightedAverageSharePriceOtherEquityInstrumentGranted" id="nyxh_WeightedAverageSharePriceOtherEquityInstrumentGranted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="FairValueOtherEquityInstrumentGranted." id="nyxh_FairValueOtherEquityInstrumentGranted." type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncrementalFairValueOtherEquityInstrumentGranted." id="nyxh_IncrementalFairValueOtherEquityInstrumentGranted." type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutSensitivityAnalysisFairValueRecoverableCashAdvancesExplanatory" id="nyxh_DisclosureOfDetailedInformationAboutSensitivityAnalysisFairValueRecoverableCashAdvancesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RecoverableCashLiabilityInterestPaid" id="nyxh_RecoverableCashLiabilityInterestPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RevenueProjectionsMember" id="nyxh_RevenueProjectionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CashGuaranteesNoncurrent" id="nyxh_CashGuaranteesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FinancialAssetsWhichCouldGenerateExchangeGainOrLossMember" id="nyxh_FinancialAssetsWhichCouldGenerateExchangeGainOrLossMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ForeignCurrencyForwardsEurUsdInEurMember" id="nyxh_ForeignCurrencyForwardsEurUsdInEurMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ForeignCurrencyForwardsEurUsdInUsdMember" id="nyxh_ForeignCurrencyForwardsEurUsdInUsdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2024Member" id="nyxh_ShareBasedPaymentArrangementsPlan2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SetUpOfProductionLineMember" id="nyxh_SetUpOfProductionLineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecondTrancheMember" id="nyxh_SecondTrancheMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ThirdTrancheMember" id="nyxh_ThirdTrancheMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BorrowingsAnnualCashInterestRate" id="nyxh_BorrowingsAnnualCashInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BorrowingsCapitalizedInterestRate" id="nyxh_BorrowingsCapitalizedInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherLongTermReceivablesExplanatoryTableTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutOtherLongTermReceivablesExplanatoryTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SyntheticWarrantMember" id="nyxh_SyntheticWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BinomialTreeMember" id="nyxh_BinomialTreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PrepaymentOptionMember" id="nyxh_PrepaymentOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LoanFacilityAgreementMember" id="nyxh_LoanFacilityAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TrancheAxis" id="nyxh_TrancheAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TrancheDomain" id="nyxh_TrancheDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SyntheticWarrantAgreementWithEuropeanInvestmentBankMember" id="nyxh_SyntheticWarrantAgreementWithEuropeanInvestmentBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsWarrantsAndRightsOutstandingTerm" id="nyxh_IfrsWarrantsAndRightsOutstandingTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsClassOfWarrantOrRightExercisePriceOfWarrantsOrRights" id="nyxh_IfrsClassOfWarrantOrRightExercisePriceOfWarrantsOrRights" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="FinancialLiabilitiesAdditions" id="nyxh_FinancialLiabilitiesAdditions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FinancingLiabilitiesIncreaseDecreaseThroughTransactionCosts" id="nyxh_FinancingLiabilitiesIncreaseDecreaseThroughTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FinancingLiabilitiesIncreaseDecreaseThroughSeparationOfNonCloselyRelatedEmbeddedDerivatives" id="nyxh_FinancingLiabilitiesIncreaseDecreaseThroughSeparationOfNonCloselyRelatedEmbeddedDerivatives" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FinancingLiabilitiesInterestRateAdjustments" id="nyxh_FinancingLiabilitiesInterestRateAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DurationUtilizedInDeterminingFairValueOfLiabilities" id="nyxh_DurationUtilizedInDeterminingFairValueOfLiabilities" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseInInvoicesToBeReceived" id="nyxh_IncreaseDecreaseInInvoicesToBeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DisclosureOfDetailedInformationAboutEmployeeBenefitsByExpenseExplanatoryTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutEmployeeBenefitsByExpenseExplanatoryTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RevenueNotRecognizedContractLiability" id="nyxh_RevenueNotRecognizedContractLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NoncurrentProvisionsForConstructiveObligation" id="nyxh_NoncurrentProvisionsForConstructiveObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ConstructiveObligationMember" id="nyxh_ConstructiveObligationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WildmanVenturesLlcMember" id="nyxh_WildmanVenturesLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncreaseDecreaseInTradeReceivable" id="nyxh_IncreaseDecreaseInTradeReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OtherFinanceCostIncludingAdjustments" id="nyxh_OtherFinanceCostIncludingAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncreaseDecreaseInOtherPayables" id="nyxh_IncreaseDecreaseInOtherPayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInResearchAndDevelopmentExpenses" id="nyxh_IncreaseDecreaseInResearchAndDevelopmentExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PercentageIncreaseDecreaseInResearchAndDevelopmentExpenses" id="nyxh_PercentageIncreaseDecreaseInResearchAndDevelopmentExpenses" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseInSellingGeneralAndAdministrativeExpenses" id="nyxh_IncreaseDecreaseInSellingGeneralAndAdministrativeExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PercentageIncreaseDecreaseInSellingGeneralAndAdministrativeExpenses" id="nyxh_PercentageIncreaseDecreaseInSellingGeneralAndAdministrativeExpenses" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExpenseShareBasedPaymentRelatedToIncrementalFairValueOfRePricedWarrants" id="nyxh_ExpenseShareBasedPaymentRelatedToIncrementalFairValueOfRePricedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ForeignCurrencySwapsAndForwardsMember" id="nyxh_ForeignCurrencySwapsAndForwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2025GrantMay52025Member" id="nyxh_ShareBasedPaymentArrangementsPlan2025GrantMay52025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfInstrumentsOtherEquityInstrumentsGrantsNumberOfDirectors" id="nyxh_NumberOfInstrumentsOtherEquityInstrumentsGrantsNumberOfDirectors" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ForeignCurrencySwapsAndForwardReceivable" id="nyxh_ForeignCurrencySwapsAndForwardReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherCurrentAssetsTableTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutOtherCurrentAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CurrentDeferredCharges" id="nyxh_CurrentDeferredCharges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DecreaseInShortTermDepositsClassifiedAsCashEquivalents" id="nyxh_DecreaseInShortTermDepositsClassifiedAsCashEquivalents" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseInCurrentAccounts" id="nyxh_IncreaseInCurrentAccounts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GainLossOnChangeInFairValueAdjustmentsOfSyntheticWarrants" id="nyxh_GainLossOnChangeInFairValueAdjustmentsOfSyntheticWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="GainLossOnChangeInFairValueAdjustmentsOfPrepaymentOption" id="nyxh_GainLossOnChangeInFairValueAdjustmentsOfPrepaymentOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2021GrantMarch242023Member" id="nyxh_SharebasedPaymentArrangementsPlan2021GrantMarch242023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2022GrantAug22024Member" id="nyxh_SharebasedPaymentArrangementsPlan2022GrantAug22024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2022Grant2Aug22024Member" id="nyxh_SharebasedPaymentArrangementsPlan2022Grant2Aug22024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2024GrantSep182024Member" id="nyxh_SharebasedPaymentArrangementsPlan2024GrantSep182024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2024GrantNov252024Member" id="nyxh_SharebasedPaymentArrangementsPlan2024GrantNov252024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2024GrantFeb12025Member" id="nyxh_SharebasedPaymentArrangementsPlan2024GrantFeb12025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2025GrantFeb12025Member" id="nyxh_SharebasedPaymentArrangementsPlan2025GrantFeb12025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2025GrantMar142025Member" id="nyxh_SharebasedPaymentArrangementsPlan2025GrantMar142025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharebasedPaymentArrangementsPlan2025GrantApr82025Member" id="nyxh_SharebasedPaymentArrangementsPlan2025GrantApr82025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2021Grant2Sept172021Member" id="nyxh_ShareBasedPaymentArrangementsPlan2021Grant2Sept172021Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2021Grant2Oct272021Member" id="nyxh_ShareBasedPaymentArrangementsPlan2021Grant2Oct272021Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareCapitalAndSharePremiumMember" id="nyxh_ShareCapitalAndSharePremiumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncreaseDecreaseInPayables" id="nyxh_IncreaseDecreaseInPayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInPayrollRelatedLiabilities" id="nyxh_IncreaseDecreaseInPayrollRelatedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInAccruedExpenses" id="nyxh_IncreaseDecreaseInAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInOtherLiabilities" id="nyxh_IncreaseDecreaseInOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EibFinanceAgreementNonCurrent" id="nyxh_EibFinanceAgreementNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="TradeReceivablesContractAssetsAndOtherReceivablesAbstract" id="nyxh_TradeReceivablesContractAssetsAndOtherReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DisclosureOfDetailedInformationAboutTradeReceivablesContractAssetsAndOtherReceivablesExplanatoryTableTextBlock" id="nyxh_DisclosureOfDetailedInformationAboutTradeReceivablesContractAssetsAndOtherReceivablesExplanatoryTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CurrentTradeReceivablesContractAssetsAndOtherReceivables" id="nyxh_CurrentTradeReceivablesContractAssetsAndOtherReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommitmentsToSuppliersForGoodsAndServices" id="nyxh_CommitmentsToSuppliersForGoodsAndServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RobertTaubAndRobelgaSrlMember" id="nyxh_RobertTaubAndRobelgaSrlMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfPatentsUnderLitigation" id="nyxh_NumberOfPatentsUnderLitigation" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="UnrealizedForeignExchangeLoss" id="nyxh_UnrealizedForeignExchangeLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueAdjustmentSyntheticWarrants" id="nyxh_FairValueAdjustmentSyntheticWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RealizedForeignExchangeLoss" id="nyxh_RealizedForeignExchangeLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="MaturityShortTermDepostisMonths" id="nyxh_MaturityShortTermDepostisMonths" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="FairValueAdjustmentPrepaymentOption" id="nyxh_FairValueAdjustmentPrepaymentOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="UnrealizedForeignExchangeGain" id="nyxh_UnrealizedForeignExchangeGain" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RealizedForeignExchangeGain" id="nyxh_RealizedForeignExchangeGain" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInOtherReceivables." id="nyxh_IncreaseDecreaseInOtherReceivables." type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RecoverableCashAdvancesMember" id="nyxh_RecoverableCashAdvancesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncreaseDecreaseInFairValueMeasurementDueToNoChangeInUnobservableInputRecognisedInProfitOrLossBeforeTaxLiabilities" id="nyxh_IncreaseDecreaseInFairValueMeasurementDueToNoChangeInUnobservableInputRecognisedInProfitOrLossBeforeTaxLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConvertibleBondsCurrent" id="nyxh_ConvertibleBondsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ConvertibleBonds" id="nyxh_ConvertibleBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInPrepayments" id="nyxh_IncreaseDecreaseInPrepayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncreaseDecreaseInCurrentTaxReceivable" id="nyxh_IncreaseDecreaseInCurrentTaxReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IfrsDebtInstrumentTerm" id="nyxh_IfrsDebtInstrumentTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsDebtInstrumentConvertibleConversionPrice" id="nyxh_IfrsDebtInstrumentConvertibleConversionPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ScheduleOfChangesInConvertibleBondsTableTextBlock" id="nyxh_ScheduleOfChangesInConvertibleBondsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsMeasurementInputConversionPriceMember" id="nyxh_IfrsMeasurementInputConversionPriceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsMeasurementInputSharePriceMember" id="nyxh_IfrsMeasurementInputSharePriceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsMeasurementInputExpectedDividendRateMember" id="nyxh_IfrsMeasurementInputExpectedDividendRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DayOneLossAmortization" id="nyxh_DayOneLossAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DayOneLossTotal" id="nyxh_DayOneLossTotal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueAdjustmentConvertibleBonds" id="nyxh_FairValueAdjustmentConvertibleBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncreaseDecreaseInFinanceExpenseDueToExchangeResults" id="nyxh_IncreaseDecreaseInFinanceExpenseDueToExchangeResults" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2025Member" id="nyxh_ShareBasedPaymentArrangementsPlan2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan20252Member" id="nyxh_ShareBasedPaymentArrangementsPlan20252Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2025GrantSep62025Member" id="nyxh_ShareBasedPaymentArrangementsPlan2025GrantSep62025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2025GrantOct132025Member" id="nyxh_ShareBasedPaymentArrangementsPlan2025GrantOct132025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LongstaffSchwartzMonteCarloMember" id="nyxh_LongstaffSchwartzMonteCarloMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RecoverableCashAdvanceAxis" id="nyxh_RecoverableCashAdvanceAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RecoverableCashAdvanceDomain" id="nyxh_RecoverableCashAdvanceDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PrepaymentOption" id="nyxh_PrepaymentOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncreaseDecreaseInPrepaymentOptionDueToFairValueAdjustment" id="nyxh_IncreaseDecreaseInPrepaymentOptionDueToFairValueAdjustment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentsPrincipalAmount" id="nyxh_DebtInstrumentsPrincipalAmount" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PrincipalInstalmentPerBondInstrument" id="nyxh_PrincipalInstalmentPerBondInstrument" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PrincipalInstalmentPerBondInstrumentLastInstalment" id="nyxh_PrincipalInstalmentPerBondInstrumentLastInstalment" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseInTradeContractAssetsAndOtherReceivables" id="nyxh_IncreaseDecreaseInTradeContractAssetsAndOtherReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentOfTotalLeaseLiability." id="nyxh_PaymentOfTotalLeaseLiability." type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInFinanceIncomeDueToFairValueAdjustmentOfDerivatives" id="nyxh_IncreaseDecreaseInFinanceIncomeDueToFairValueAdjustmentOfDerivatives" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DepreciationInForeignExchangeRatePercent" id="nyxh_DepreciationInForeignExchangeRatePercent" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2024GrantJune262026Member" id="nyxh_ShareBasedPaymentArrangementsPlan2024GrantJune262026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan2025GrantJune262026Member" id="nyxh_ShareBasedPaymentArrangementsPlan2025GrantJune262026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementsPlan20252GrantJune262026Member" id="nyxh_ShareBasedPaymentArrangementsPlan20252GrantJune262026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CashGuaranteesMember" id="nyxh_CashGuaranteesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NewLeaseAgreements." id="nyxh_NewLeaseAgreements." type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInAmortizationDay1LossConvertibleBond" id="nyxh_IncreaseDecreaseInAmortizationDay1LossConvertibleBond" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueAdjustmentForeignCurrencySwapsAndForwards." id="nyxh_FairValueAdjustmentForeignCurrencySwapsAndForwards." type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseThroughVestedRestrictedStockUnitShareBasedPaymentsModification" id="nyxh_IncreaseDecreaseThroughVestedRestrictedStockUnitShareBasedPaymentsModification" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EibAccruedInterestCurrent" id="nyxh_EibAccruedInterestCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
</xsd:schema>
