Pharmacotherapy and psychotherapy in cannabis withdrawal and dependence.

Cannabis has long been perceived as a drug causing questionable dependence. Only recently has a clinically recognized withdrawal syndrome been described, thus laying the foundations for specific treatment evaluations. Six different pharmacotherapies have been studied in cannabis withdrawal. Of these, only oral tetrahydrocannabinol, and perhaps mirtazapine, have shown some promise in the specific treatment of withdrawal symptoms. In cannabis dependence, rimonabant, and perhaps buspiron, have shown promising results. Clinical trials of oral tetrahydrocannabinol were less convincing. Cognitive and behavioral therapies and motivational enhancement therapies have proven their efficacy in several randomized controlled trials. Brief therapies have also been associated with good compliance and efficacy. Combinations with voucher incentives in certain populations have been associated with improved treatment compliance and reduced cannabis use. Only two studies have analyzed the cost-efficacy of psychotherapies. It would seem that brief combined cognitive and behavioral therapies, and motivational enhancement therapies are the most cost effective. For the moment, it is uncertain whether the additional treatment costs associated with voucher incentives are proportional to the accrued abstinence duration.