About Nicorandil A potassium channel opener,a vasodilator, Antianginal. Mechanism of Action of Nicorandil The drug exerts antianginal action by activating ATP sensitive potassium channels which leads to hyperpolarizing vascular smooth muscle and ultimate vasodilatation. It also acts as a nitric oxide donor relaxes blood vessels by increasing cyclic GMP and hence arterial dilatation is coupled with venodilatation. Dilatations of both epicardial conducting vessels and deeper resistance vessels have occurred and coronary flow is increased. Improves exercise tolerance and reduce frequency of angina. Mitochondrial K+ATP channel opening by Nicorandil also exerts myocardial protection by a process of ischaemic preconditioning which reduce myocardial stunning, arrhythmias and infarct size when a coronary artery is suddenly blocked. Myocardial recovery from ischaemic damage after myocardial infarction as measured by left ventricular wall motion is improved by Nicorandil.