The search for medications to treat amphetamine and methamphetamine dependence started much more recently than that for cocaine treatment medications. Consequently, fewer medications have been tested. Similarities between the mechanisms of action of amphetamine and methamphetamine and those of cocaine suggest that the same medications may help with both dependencies. Hence, several of the medications that have been discussed are undergoing, or about to undergo, testing for methamphetamine dependence. For instance, trials of topiramate and modafinil are planned.
Bupropion is an antidepressant medication that is also effective in smoking cessation. Bupropion’s efficacy for these uses rests upon its ability to support positive mood by inhibiting the reuptake of dopamine into cells, leaving more of the neurotransmitter circulating in the mesolimbic system. The same mechanism may be helpful in easing the negative mood symptoms of methamphetamine withdrawal.
Although studies have shown bupropion to be ineffective in treating cocaine dependence, a recent clinical trial suggested that it may have promise for methamphetamine dependence. Among 151 methamphetamine-dependent patients, bupropion recipients had somewhat better abstinence outcomes compared with placebo recipients; the difference approached, but did not quite achieve, statistical significance. In a subgroup of patients whose methamphetamine use at baseline was less intensive, however, bupropion treatment was associated with significantly more weeks of abstinence (Elkashef et al., 2007).
Bupropion is fairly well-tolerated. Common side effects include insomnia, agitation, dry mouth, and nausea. This medication is contraindicated in patients with seizure disorders, current or prior diagnoses of bulimia or anorexia nervosa, or concurrent treatment with (or within 14 days of discontinuation of) monoamine oxidase inhibitors. Bupropion should not be used in patients detoxifying from alcohol or sedatives.