 Acecainide is pharmacologically active as an antiarrhythmic agent.It has electrophysiological effects of a class III antiarrhythmic drug and it is used as a medicine to increase the Q – T interval of the PQRST heart rhythm in patients with cardiac arrhythmias.The equivalent drug procainamide, which is a class Ia antiarrhythmic drug, is also used in patients with cardiac arrhythmias.