The main effect of nifedipine is to prevent calcium ions from entering the cell from outside the cell, thus effectively reducing the intracellular calcium ion concentration. First, for cardiomyocytes, the effect of nifedipine reduces the amount of calcium ions entering the cell from outside the cell, with the end result that the intracellular calcium ion concentration decreases, which inhibits myocardial contraction and reduces myocardial oxygen consumption. Secondly, for blood vessels, nifedipine can also prevent calcium ions from entering into vascular smooth muscle cells, thus causing vasodilation, mainly of arterial vessels, which can increase blood supply to ischemic areas for heart vessels, especially for patients with coronary spasm. Thirdly, for the peripheral blood vessels, the vasodilating effect can reduce the peripheral vascular resistance and thus lower the blood pressure, both systolic and diastolic.