AnalgesicsAnalgesiaPainAnalgesics, OpioidPain MeasurementPain ManagementPain, PostoperativeAnalgesics, Non-NarcoticMorphineTramadolPhenacetinAcetaminophenDextropropoxypheneAnti-Inflammatory Agents, Non-SteroidalDrug ToleranceCodeinePain ThresholdMeperidineFentanylPentazocineReceptors, Opioid, muOxycodoneAnesthetics, LocalDipyroneHyperalgesiaInjections, SpinalBupivacaineAnalgesia, EpiduralNaloxoneDouble-Blind MethodAnalgesia, Patient-ControlledCarrageenanKetoprofenKidney Papillary NecrosisTolmetinNefopamReceptors, OpioidHydrocodoneNarcotic AntagonistsKetorolacPain, IntractableIbuprofenNociceptionNeuralgiaHydromorphoneDose-Response Relationship, DrugNalorphineAcupuncture AnalgesiaCyclohexanecarboxylic AcidsBuprenorphineEdemaNociceptorsDiclofenacAnalgesia, ObstetricalButorphanolOxymorphoneMorphine DerivativesMorphinansMeptazinolNociceptive PainHypnotics and SedativesNarcoticsAlfentanilAntipyreticsKetamineAcetic AcidNalbuphineAcute PainNerve BlockChronic PainRats, Sprague-DawleyDexmedetomidineCyclazocineKetorolac TromethamineSufentanilLidocaine