DextromethorphanQuinidineDextrorphanAntitussive AgentsLevorphanolCytochrome P-450 CYP2D6Oxidoreductases, O-DemethylatingGuaifenesinDebrisoquinCytochrome P-450 Enzyme SystemCodeinePseudobulbar PalsyChlorpheniraminePerhexilineGastric DilatationMorphinansMicrosomes, LiverExcitatory Amino Acid AntagonistsDealkylationReceptors, sigmaMixed Function OxygenasesExpectorantsMemantineCoughCytochrome P-450 CYP3AAporphinesReceptors, N-Methyl-D-AspartateQuinineDrug Interactions