Background: Treatment-emergent mania/hypomania (TEM) is a possible adverse effect of pharmacological and non-pharmacological antidepressant treatments. Objective: We performed a systematic review and meta-analysis to evaluate the risk of TEM in depressed patients during randomized, sham-controlled trials (RCTs). Data sources: Medline database, from the first date available to August 12, 2016. Results: From 283 references, 10 RCTs were identified. Only 3 of them described TEM. In active and sham groups, respectively, only 8 of 226 (3.5%) and 1 of 190 (0.5%) participants presented TEM. This difference was not statistically significant (OR = 1.79, 95% CI = 0.6 to 5.32). There were also five additional reports of TEM in participants not on RCTs. No risk factors for TEM were identified. Limitations: Low number of studies and TEM reports. Conclusion: Despite previous reports, active vs. sham tDCS was not associated with a significantly greater number of TEM episodes. (C) 2016 Elsevier Inc. All rights reserved.