About nifedipinea dihydropyridine calcium channel blocker, antianginal, antihypertensive,tocolytic.mechanism of action of nifedipinenifedipine is a dihydropyridine ca channel blocker. it exerts it`s antianginal, antihypertensive actions through blocking the influx of ca2+ ions through voltage gated l-type ca channels to the peripheral vascular smooth muscle cells, coronary smooth muscle cells and to the myocardial cells. thus causes dilatation of vascular endothelium, decrease peripheral resistance, & reduce myocardial oxygen demand .it markedly relax arterioles and milder effects on veins, decrease after load and increase cardiac index. it do not compromise haemodynamics and cerebral and renal perfusion. it inhibits platelet aggregation and relaxes bronchial, uterine, and ureteric smooth muscles. it is an effective uterine relaxant agent. migraine: it is used in migraine by reducing intracellular ca+2 overload due to brain hypoxia and other causes.