Background: Domperidone is widely prescribed in patients with gastrointestinal disorders but some cardiac adverse effects have been recently reported. Aim: To evaluate the risk of QT prolongation, ventricular arrhythmias and sudden cardiac death associated with the use of oral domperidone in adults without cancer. Material and methods: Systematic searches in MEDLINE, LILACS, ScIELO, the Cochrane Library and regulatory agencies websites were performed, followed by a manual search of cited references. The search strategy consisted of combining free and indexed text words without any date or language restriction. Results: Three case-control studies met the inclusion criteria; none of them evaluated QT interval prolongation. With low risk of bias, each study quantified the risk of ventricular arrhythmia or sudden cardiac death (VA/SCD). The odds ratios for these events in these studies were 4.7 (95% confidence interval (CI): 1.4-16), 1.59 (95% CI: 1.28-1.98) and 11.02 (95% CI: 2.02-62.3) respectively. A significantly increased risk was observed in patients older than 60 years of age or receiving doses > 30 mg/day. Conclusions: Heterogeneity between selected studies did not allow the computation of a summary measure. However, evidence was found that an increased risk of VA/SCD is associated with the use of oral domperidone in adults.CARDIAC ADVERSE EFFECTS OF DOMPERIDONE IN ADULT PATIENTS: A SYSTEMATIC REVIEW Background: Domperidone is widely prescribed in patients with gastrointestinal disorders but some cardiac adverse effects have been recently reported. Aim: To evaluate the risk of QT prolongation, ventricular arrhythmias and sudden cardiac death associated with the use of oral domperidone in adults without cancer. Material and methods: Systematic searches in MEDLINE, LILACS, ScIELO, the Cochrane Library and regulatory agencies websites were performed, followed by a manual search of cited references. The search strategy consisted of combining free and indexed text words without any date or language restriction. Results: Three case-control studies met the inclusion criteria; none of them evaluated QT interval prolongation. With low risk of bias, each study quantified the risk of ventricular arrhythmia or sudden cardiac death (VA/SCD). The odds ratios for these events in these studies were 4.7 (95% confidence interval (CI): 1.4-16), 1.59 (95% CI: 1.28-1.98) and 11.02 (95% CI: 2.02-62.3) respectively. A significantly increased risk was observed in patients older than 60 years of age or receiving doses > 30 mg/day. Conclusions: Heterogeneity between selected studies did not allow the computation of a summary measure. However, evidence was found that an increased risk of VA/SCD is associated with the use of oral domperidone in adults.