Caffeine potentiation of amphetamine: implications for hyperkinesis therapy.

Neither 0.05 mg/kg d-amphetamine nor 15 mg/kg caffeine alone produce amphetamine-like responding in rats trained in two-lever operant chambers to discriminate 0.8 mg/kg d-amphetamine from saline. The co-administration of the two drug doses produced responding similar to the 0.8 mg/kg d-amphetamine dose. A suggestion for the mechanism of action and a regimen of administration for caffeine in hyperkinetic children are discussed.