The Effect of High-frequency Repetitive Transcranial Magnetic Stimulation on Reducing Depression and Anxiety in Methamphetamine Users

Background: Methamphetamine use has been associated with higher rates of depression and anxiety. The mesocorticolimbic dopaminergic reward system seems to play a crucial role in inducing depression and anxiety in methamphetamine users. High-frequency repetitive transcranial magnetic stimulation (rTMS) has been shown to alter dopaminergic neurotransmission considering the acute rewarding and reinforcing effects in the subcortical structure. The aim of this study was to investigate the efficacy of rTMS in reducing depression and anxiety symptoms in methamphetamine users. Methods: In a single-subject method with concurrent multiple baseline designs, in 2017, in Iran, eight methamphetamine users were included, which compared 15 days of active versus placebo stimulation and control group. Two subjects received rTMS on the right dorsolateral prefrontal cortex (DLPFC) and two subjects received rTMS on the left DLPFC. We carried out the measurement using the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) before, during, and after 15 and 30 days of the procedure. Findings: Right and left DLPFC stimulation significantly reduced depression and anxiety, but the reduction of depression and anxiety by the right DLPFC stimulation was noticeable in this study. Conclusion: High-frequency rTMS is useful for the treatment of depression and anxiety in methamphetamine users.