The effects of mazindol, cocaine and D-amphetamine were studied in rhesus monkeys trained to self-administer cocaine, and in rats and squirrel monkeys trained to discriminate cocaine from saline. Non-contingent intravenous drug injections were administered to monkeys responding under a session consisting of a 5-min period during which lever-pressing produced food reinforcement and a 60-min session in which responding produced i.v. cocaine infusions (10 or 33 micrograms/kg per infusion). Acute i.v. injections of cocaine (0.1-1.7 mg/kg), D-amphetamine (0.1-1 mg/kg) and the dopamine re-uptake inhibitor mazindol (0.03-0.56 mg/kg) given 5 min before the session decreased self-administration of cocaine, but also decreased rates of behavior maintained by the presentation of food. In both rats and squirrel monkeys trained to discriminate cocaine from saline in a two-lever, food-maintained procedure, mazindol, cocaine and D-amphetamine substituted for cocaine in a dose-related manner. Despite a lack of selectivity to decrease cocaine self-administration as compared to behavior maintained by food, the present data provide some rationale for further consideration of mazindol as a potential pharmacotherapy for stimulant abuse, due to its relatively low abuse liability and cocaine-like discriminative stimulus effects.