Background: Hydroxychloroquine (HCQ) is currently being examined for COVID-19. No previous meta-analysis has evaluated its side effects versus placebo. We conducted this meta-analysis to compare the safety of HCQ versus placebo. Methods: Two authors independently searched PubMed and EMBASE databases for randomized controlled trials (RCTs) of adults comparing the adverse events (AEs) of HCQ versus placebo for any indication. Peto odds ratios (Peto ORs) and 95% confidence intervals (CIs) were calculated based on random-effects models. The heterogeneity (I 2) was assessed using Cochran's Q test. Results: Nine RCTs (eight were double-blind) with a total of 916 patients were included. HCQ caused significantly more skin pigmentation than placebo