RESUMO
We report a case of a patient with acute pancreatitis who developed serious heart rhythm abnormalities on three occasions, two of which were associated with administration of the first generation antihistamine chloropyramine, and the third one with hypomagnesemia and hypokalemia. Dysrhythmic events consisted of bigeminy, multifocal ventricular extrasystoles and torsades de pointes-like ventricular tachycardia. Electrocardiographic changes in acute pancreatitis in the absence of previous heart disease can occur in more than half of the cases. Antihistamines are medications that are known to produce heart rhythm disturbances, especially the second generation drugs astemizole and terfenadine. This is the first report of chloropyramine causing dysrhythmia. It seems that acute pancreatitis patients are especially prone to heart dysrhythmia caused by different factors such as electrolyte disturbances and pronounced vagal tone. Acute pancreatitis may be added to the list of risk factors with altered 'repolarization reserve', predisposing to drug-induced QT interval prolongation and possible torsades de pointes occurrence.