Disclosed are methods and compositions which may be used in human cytochrome P450 (CYP450) enzyme phenotyping. The methods and compositions typically utilize a melange of substrates for different CYP450 enzymes which may be administered orally to a patient. Subsequently, the metabolites of the substrates may be detected in the patient's saliva as well as any non-metabolized substrates to calculate a metabolic ratio for any given CYP450 enzyme in order to generate a phenytopic CYP450 enzyme profile for the patient.