BEHAVIORAL AND CARDIOVASCULAR EFFECTS OF INTRAVENOUS METHYLPHENIDATE IN NORMAL SUBJECTS AND COCAINE ABUSERS

This study compares the behavioral and cardiovascular response to meth ylphenidate (0.5 mg i.v.) in 10 cocaine abusers and 20 controls. Methy lphenidate induced a long-lasting increase in blood pressure and pulse rate in both groups of subjects. It also induced a short-lasting 'hig h' (27 min) and longer-lasting 'restlessness' (67 min). In the normal subjects, but not in the cocaine abusers, methylphenidate significantl y increased sexual desire and induced a subjective experience of 'loss of control'. In the cocaine abusers, methylphenidate consistently ind uced cocaine craving. While 90% of the cocaine abusers reported methyl phenidate as pleasurable, only 50%, of the normal subjects did. Cocain e abusers reported that the 'high' induced by methylphenidate was simi lar to that of cocaine but lasted longer and was associated with more physical effects.