ETHANOL EFFECTS ON SELF-ADMINISTRATION OF ALFENTANIL, COCAINE, AND NOMIFENSINE IN RHESUS-MONKEYS

A common form of polydrug use is that of cocaine and ethanol. The iden tification of an ethanol-cocaine combination product, cocaethylene, wi th properties in common with cocaine, has led to speculation that this metabolite may contribute to the co-abuse of cocaine and ethanol. In order to determine whether ethanol pretreatments selectively altered c ocaine's reinforcing potency, ethanol pretreatments were given to monk eys trained to press levers and receive IV infusions of several doses of cocaine or alfentanil. In addition, nomifensine, a drug which has a mechanism of action similar to cocaine's, was evaluated in the presen ce and absence of ethanol in monkeys with the cocaine baseline history . Ethanol, in doses ranging from 100 to 1780 mg/kg, given 10 min befor e the 130-min session, had no effect on responding maintained by alfen tanil. These doses also had no significant effect on cocaine-maintaine d responding, although the potency of cocaine as a reinforcer was incr eased following administration of 1000 mg/kg ethanol in two of the fou r subjects. The potency of nomifensine as a reinforcer was significant ly increased by 1000 mg/kg ethanol, but again, this enhancement was li mited to the same two subjects. These data indicate that, in this para digm, cocaethylene did not selectively modify cocaine's reinforcing po tency, but there appear to be individual differences with respect to e thanol's ability to stimulate rates of drug-maintained responding.