Disopyramide is class Ia anti arrhythmic agent. Disopyramide is mostly used in treating patient with ventricular dysrhythmia and supraventricular dysrhythmia.
Disopyramide is administered orally or via intravenous solution. Half of disopyramide will be metabolized in the hepatic system while half of disopyramide will remain unchanged and excreted by the kidney.
Disopyramide will block the opening of the Na+ channel and lead to inactivation of the sodium ion channel in the cell membrane. This will cause and increase in the effective refractory period with slow AV conduction due to reduction in the rate of phase 0 depolarisation. There will also slowness in the repolarisation of the action potential. The half life of disopyramide is approximately 5 hours to 10 hours.
Disopyramide may produce side effects such as dry mouth, constipation, blurred vision and urinary retention. Disopyramide may produce side effects associated with negative inotropic action. In certain cases, disopyramide may lead to the development of torsade de pointes.