The subjective, behavioral and physiological effects of modafinil (300 mg PO) a new central adrenergic stimulant, were compared with those of dextroamphetamine (15 mg PO), caffeine (300 mg PO) and placebo in a randomized double-blind cross-over study. Sixteen healthy volunteers participated in the study y: 8 males and 8 females with no history of drug abuse and moderate use of caffeine. Subjective and behavioral effects were studied using the Addiction Research Center Inventory (ARCI), Profile of Mood States (POMS) and Visual Analog Scales before and 1, 2, 4 and 8 h post single oral dosing. Results showed that subjective effects of modafinil (300 mg) differed markedly from those of dextroamphetamine (15 mg). They were close to those produced by caffeine (300 mg). These results indicate that modafinil (300 mg) does not possess amphetamine-like subjective effects in a healthy population. If subjective feelings are related to drug abuse liability, it could be assumed that modafinil, at the dose used in therapeutics, does not possess any abuse liability comparable to amphetamine.
