Use of calcium ion entry blockers in family practice.

Verapamil, nifedipine, and diltiazem are drugs which decrease intracellular calcium in cardiac muscle, smooth muscle, and nodal cardiac cells. Unlike B-blockers, each drug acts at a different site on the cell membrane and has an important difference in overall action. Verapamil is used to treat angina, systemic hypertension, hypertrophic cardiomyopathy, and supraventricular and junctional tachyarrhythmias. Nifedipine is useful in angina, vasospastic disorders, and hypertension. A specific role for diltiazem is now being defined.