Nifedipine in Hypertension: Expanding Applications of a New Drug

During the last decade, a new class of calcium-inhibiting drugs has been applied in the treatment of symptomatic coronary artery disease. These compounds seemingly inhibit the inward passage of calcium across myocardial and vascular smooth-muscle cells and probably interfere with the intracellular release of calcium. The net effect of the calcium inhibitor is to uncouple the excitation-contraction process, causing smooth-muscle relaxation. 1 Hemodynamic effects include a reduction in coronary artery and peripheral vascular resistances. Several calcium-inhibiting drugs also depress myocardial contractility, while others affect the electrical conduction system of the heart. These drugs have been used successfully in the treatment of chronic exertional angina, coronary spasm, and supraventricular tachycardia. Nifedipine, methyl-1,4 dihydro-2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridinedicarboxylate, is a calcium inhibitor that can be administered orally and sublingually. The hemodynamic and metabolic effects can be summarized as follows: (1) decrease in left ventricular systolic and diastolic pressures, (2) decrease in mean arterial pressure, (3) decrease