Mirtazapine in amphetamine detoxification: A placebo-controlled pilot study

The present study aimed to assess the safety and efficacy of mirtazapine in amphetamine detoxification in a 14-day randomized, placebo-controlled pilot trial in a Thai population. Subjects retained at a Specialized Probation Center, Department of Probation, Ministry of Justice, Thailand (n=20), who met DSM-IV criteria for amphetamine dependence and the inclusion criteria of the study, were randomized for either mirtazapine treatment or placebo. Efficacy was assessed by the Amphetamine Withdrawal Questionnaire (AWQ) for amphetamine withdrawal symptoms and the Montgomery-Åsberg Depression rating scale (MADRS) for depression. Mirtazapine safety was assessed by interview during each follow-up period on days 3 and 14 after treatment. Nine subjects were randomized to the mirtazapine group and 11 to the placebo group. Among the initial 20 subjects, 16 (seven in the mirtazapine and nine in the placebo group) completed the study. There were significant improvements in the total AWQ score changes in the mirtazapine group versus placebo both at days 3 (P<0.005) and 14 (P<0.030). Significant improvements in favour of mirtazapine were also seen in the hyperarousal and the anxiety subscale score changes at days 3 (P<0.029) and 14 (P<0.018), respectively. No significant differences were seen (P>0.05) in the MADRS scores changes within or between the groups. Mild adverse events, such as headache, sedation, nausea and vomiting, were reported. In conclusion, despite its small sample size, this randomized, placebo-controlled pilot trial lends support to the hypothesis that mirtazapine may be an option in the meager armamentarium of amphetamine detoxification treatment.