HydrocodoneCocaineHydromorphoneOxycodoneCodeineAnalgesics, OpioidOxymorphoneObstetric Surgical ProceduresSubstance Abuse DetectionMorphine DerivativesNarcoticsCocaine-Related DisordersAntitussive AgentsMiosisCytochrome P-450 CYP2D6Gas Chromatography-Mass SpectrometryOpioid-Related DisordersAcetaminophenDopamine Uptake InhibitorsMorphineCrack CocainePain, PostoperativeSelf Administration