Background: Substance use disorders (SUDs) and Gambling Disorder (GD) are addictive disorders with a chronic course. Given the limited efficacy of conventional treatments, there is increasing interest in alternative strategies targeting the altered neural circuits associated with the disease. In this context, deep Transcranial Magnetic Stimulation (dTMS) has emerged as a novel neuromodulation technique capable of reaching deep brain regions. However, no definite recommendation for its use in addiction treatment exists. This study systematically reviewed and quantitatively analyzed dTMS effects in SUDs and GD populations. Methods: Following the PRISMA guidelines, we screened four electronic databases up to February 2024 and selected relevant English-written original research articles. 17 papers were included in the systematic review. As only a minority of studies employed a sham-controlled design, we ran the meta-analysis on a subset of 12 studies, computing the pre-post real stimulation standardized mean change (SMCC) as the effect size, using self-reported craving scores as the dependent variable. Results: The results showed a significant and large effect of active dTMS in reducing craving scores (SMCC = - 1.26, 95% CI [-1.67, - 0.86], p <.001). High heterogeneity at both quantitative and qualitative levels across studies was found, with research focusing on different types of SUDs and only one study on gambling behaviors. Conclusions: Results provide initial evidence of the feasibility of dTMS for SUDs care. However, further comprehensive research is needed to unveil several methodological challenges. The limitations of the available literature and future research directions are critically discussed.

We declare that L.D.M. works as a psychologist at Fondazione Eris ETS, and L.J.R.L. is a consultant for Fondazione Eris ETS, a non-profit organization dedicated to addiction rehabilitation through a multidisciplinary approach, including applying dTMS.

This study did not receive any funding

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The study is a meta-analysis, therefore data included and analyzed are already available.