Combination of chlorpromazine (CPZ) and verapamil (Ver) was found to decrease the incidence of ventricular arrhythmias and ventricular fibrillation induced by myocardial ischemia and reperfusion, lower serum creatine phosphokinase (CPK) and decrease the content of malondialdehyde (MDA) in heart tissue homogenate especially in mitochondria; and increase the phospholipid content and the phospholipid/cholesterol ratio; and decrease the myocardial "cell calcium" content in the reperfused area. The effect of CPZ and Ver combination was better than either CPZ and Ver alone.