DOPAMINERGIC RESPONSIVITY DURING COCAINE ABSTINENCE - A PILOT-STUDY

This preliminary study investigated dopamine (DA) function in six hospitalized cocaine-dependent subjects (DSM-III-R) who received 1.5 mg/kg of active cocaine by mouth, t.i.d., for 3 days followed by 9 days of placebo cocaine. During early and late abstinence from cocaine, plasma growth hormone (GH), homovanillic acid (HVA), prolactin, and 3-methoxy-4-hydroxyphenethylene-glycol responses to the placebo-controlled administration of oral L-dopa 250 mg/carbidopa 25 mg (Sinemet(R)) were measured. Sinemet caused significantly greater placebo-corrected increases in GH and HVA during early as compared with late abstinence. Acute abstinence from cocaine may be associated with increased DA responsivity, which normalizes over time.