BACKGROUND Bulimia nervosa (BN) patients are characterized by binge eating followed by compensatory behaviors. Ingestion of emetic substances, characteristic to some BN patients, has been reported to be associated with supraventricular arrhythmias. OBJECTIVE To evaluate atrial electrocardiographic markers for supraventricular arrhythmias in patients with BN. METHODS The cohort included 31 patients with BN and sex- and age-matched controls. Twelve-lead electrocardiography was conducted on all participants under strict standards. P wave length and P wave dispersion in each patient were computed from a randomly selected beat and an averaged beat constructed from 7-12 beats, included in a 10-s ECG. RESULTS No statistically significant differences were found between the groups for minimal, maximal, and average P wave duration and P wave dispersion, calculated either from a random beat or averaged beats. CONCLUSIONS BN patients who are medically monitored and treated, have normal P wave parameters and P wave dispersion, and therefore do not appear to have an increased risk for developing supraventricular arrhythmias. Future research should focus on evaluating the effect of acute ingestion of emetic drugs on resting ECG of BN patients, as well as using signal averaging techniques and prolonged ECG-Holter monitoring.