Successful Use of Minocycline for the Treatment of Methamphetamine-Induced Psychosis and Cognitive Impairments: An Open-Label Case Series.

Abstract

Methamphetamine-induced psychosis and neuropsychological impairments are common among patients with methamphetamine use disorder. Given some preclinical and clinical studies reporting potential effects of minocycline, a second-generation tetracycline, on correcting manifestations of drug addiction, this study aimed to examine the effectiveness of minocycline in attenuating psychotic symptoms and neuropsychological impairments in chronic methamphetamine users. Five men with treatment-resistant methamphetamine use disorder and psychotic symptoms were selected using a convenience sampling method, and they were administered a daily dose of 200-mg minocycline for 8 weeks; within this period, psychiatric and neuropsychological assessments (including memory and executive functions) were carried out at the baseline, week 2, week 4, week 8, and 2-month follow-up. The findings showed that minocycline attenuated both positive (Cohen d = 0.63) and negative (Cohen d = 0.53) methamphetamine-induced psychotic symptoms and also improved patients' neuropsychological functions, particularly their auditory working memory (Cohen d = 0.45). These results provide promising evidence regarding the positive effects of minocycline as adjunctive pharmacotherapy for patients with methamphetamine use disorder. However, given that this was an open-label study, further research is warranted to draw a firm conclusion about the effectiveness of minocycline for methamphetamine-induced psychosis and neuropsychological deficits.