Acecainide is an active metabolite of the class III antiarrhythmic procainamide. It is formed from procainamide via hepatic N-acetyltransferases. Acecainide prevents hypoxia-induced ventricular fibrillation in mice and decreases arrhythmia induced by aconitine in dogs. Acecainide (10 ?M), when used in high-fat medium, decreases lipid droplet area by greater than 50% in SK-Hep1 cells without inducing cytotoxicity but does not affect lipid droplets in primary mouse hepatocytes.