AnalgesicsNarcoticsNalorphineAnalgesics, OpioidLevallorphanMeperidinePentazocineDextropropoxypheneLevorphanolMorphineAlphaprodinePainMorphinansCyclazocineAnalgesics, Non-NarcoticAnalgesiaPapaverDipyroneTramadolFentanylDrug and Narcotic ControlPain MeasurementMethadoneIsonipecotic AcidsPain, PostoperativeNaloxoneAcetaminophenHydromorphoneNarcotic AntagonistsDextromoramidePhenacetinDrug ToleranceKetoprofenAnti-Inflammatory Agents, Non-SteroidalOpiumCodeinePain ManagementReceptors, Opioid, muHyperalgesiaOxymorphoneNociceptionLegislation, DrugOpioid-Related DisordersPain ThresholdOxycodoneHydrocodoneSphincter of OddiHeroinPreanesthetic MedicationNeuralgiaDose-Response Relationship, DrugPain, IntractableNociceptorsDouble-Blind MethodAnesthetics, LocalDrug Evaluation, PreclinicalBupivacaineReceptors, OpioidButorphanolAnalgesia, Patient-ControlledAlfentanilSubstance-Related DisordersAspirinSpasmMorphine DerivativesBuprenorphineTime FactorsInert Gas NarcosisChronic DiseaseMethotrimeprazineEndorphinsNitrous OxideMorphine DependenceVocalization, AnimalAlcoholics AnonymousMitragynaAnesthesiaNaltrexoneProspective StudiesHypnotics and SedativesSpinal CordInjections, SpinalRats, Sprague-DawleyNerve BlockDrug OverdoseParamethasoneKetonesBridged CompoundsIndomethacinAnalgesia, EpiduralSubstance Withdrawal SyndromeArthritis, ExperimentalDibenzocycloheptenesAnestheticsTreatment OutcomeInfusion PumpsCarrageenanDisease Models, AnimalMethadyl AcetatePharmacy