Pharmacology of angiotensin converting enzyme inhibitors. A review

Two angiotensin converting enzyme inhibitors are currently available for clinical use. Captopril, a sulfhydryl-containing compound, is a direct acting enzyme inhibitor. Enalapril is a non-sulfhydryl pro-drug that requires enzymatic conversion to enalaprilic acid, a potent angiotensin converting enzyme inhibitor. Both drugs lower blood pressure, suppress blood pressure response to angiotensin I infusion, and elevate plasma renin activity. Enalapril bioavailability is unaffected by food, whereas captopril availability is suppressed by food. Dose adjustments are necessary for patients with congestive heart failure and renal failure.