A double-blind placebo-controlled trial of N-acetylcysteine in the treatment of cocaine dependence.

BACKGROUND: There remains no FDA approved medication for the treatment of cocaine dependence. Preclinical studies and early pilot clinical investigations have suggested that N-acetylcysteine (NAC) may be useful in the treatment of the disorder. OBJECTIVE: The present report assessed the efficacy of NAC in the treatment of cocaine dependence. METHODS: Cocaine-dependent volunteers (n = 111) were randomized to receive daily doses of 1,200 mg of NAC, 2,400 mg of NAC, or placebo. Participants were followed for 8 weeks (up to three visits weekly). At each of these visits, urine samples were collected, along with self-reports of cocaine use. Urine samples were assessed for quantitative levels of benzoylecognine (ie, cocaine metabolite). RESULTS: Overall, the primary results for the clinical trial were negative. However, when considering only subjects who entered the trial having already achieved abstinence, results favored the 2,400 mg NAC group relative to placebo, with the 2,400 mg group having longer times to relapse and lower craving ratings. CONCLUSION: While the present trial failed to demonstrate that NAC reduces cocaine use in cocaine-dependent individuals actively using, there was some evidence it prevented return to cocaine use in individuals who had already achieved abstinence from cocaine. SCIENTIFIC SIGNIFICANCE: N-acetylcysteine may be useful as a relapse prevention agent in abstinent cocaine-dependent individuals.

An open-label trial of N-acetylcysteine for the treatment of cocaine dependence: a pilot study.

Recent preclinical studies implicate N-acetylcysteine (NAC), a cysteine prodrug, as a potential medication for preventing relapse to cocaine use; however, little is known about the safety and tolerability of NAC in cocaine-dependent subjects in an outpatient setting. This pilot study examines the safety and tolerability of 3 doses of NAC for the treatment of cocaine dependence. Twenty three treatment-seeking cocaine-dependent patients participated in a 4-week medication trial and received NAC at doses of 1200 mg/day, 2400 mg/day or 3600 mg/day. Results suggested that the three doses were well tolerated. Overall, the retention rates appeared to favor higher doses of NAC (2400 mg/day and 3600 mg/day). The majority of subjects who completed the study (n=16) either terminated use of cocaine completely or significantly reduced their use of cocaine during treatment. Overall the findings suggest that it is feasible to treat cocaine-dependent treatment seekers with N-acetylcysteine on an outpatient basis.