NarcoticsAnalgesicsNalorphineLevallorphanAnalgesics, OpioidMeperidinePentazocineDextropropoxypheneLevorphanolAlphaprodineMorphineMorphinansCyclazocinePapaverFentanylDrug and Narcotic ControlAnalgesics, Non-NarcoticMethadoneIsonipecotic AcidsPainNaloxoneAnalgesiaNarcotic AntagonistsPain, PostoperativePain MeasurementOpiumCodeineOxymorphoneLegislation, DrugOpioid-Related DisordersTramadolDrug ToleranceOxycodoneAcetaminophenHydrocodonePhenacetinHeroinPreanesthetic MedicationPain ManagementHydromorphonePain, IntractableReceptors, Opioid, muAnesthetics, LocalBupivacaineReceptors, OpioidButorphanolAnti-Inflammatory Agents, Non-SteroidalAnalgesia, Patient-ControlledAlfentanilSubstance-Related DisordersSpasmMorphine DerivativesBuprenorphinePain ThresholdInert Gas NarcosisMethotrimeprazineEndorphinsNitrous OxideDose-Response Relationship, DrugMorphine DependenceDouble-Blind MethodAlcoholics AnonymousMitragynaAnesthesiaNaltrexoneDipyroneHyperalgesiaHypnotics and SedativesInjections, SpinalNerve BlockDrug OverdoseParamethasoneKetonesBridged CompoundsAnalgesia, EpiduralSubstance Withdrawal SyndromeDibenzocycloheptenesTime FactorsAnestheticsTreatment OutcomeInfusion PumpsCarrageenanMethadyl AcetatePharmacyKetoprofenKidney Papillary NecrosisNeonatal Abstinence SyndromeTolmetinNefopamKetorolacFuransIbuprofenPerphenazineEnkephalinsNociceptionNeuralgiaPalliative CareDrug PrescriptionsPhenanthrenesGastrointestinal Diseases