Diltiazem: its place in the antihypertensive armamentarium

In 15 randomized, double-blind studies with blood pressure measured at the end of the dosing interval, diltiazem sustained-release or conventional tablets were found to be equal in efficacy to hydrochlorothiazide, beta-blockers, angiotensin-converting enzyme inhibitors, and other calcium-channel antagonists. The total number of patients with adverse effects and those who drop out due to adverse effects are similar for diltiazem and the other drugs. Combination therapy with diltiazem and captopril showed additive effects, and combination of diltiazem with hydrochlorothiazide or atenolol showed additional, but perhaps less than additive, effects. Six studies in older and younger patients have shown no overall effect of age on the antihypertensive effect of diltiazem. Two studies showed no difference in mean antihypertensive response between black and non-black patients. In contrast to diuretics and beta-blockers, diltiazem does not have adverse metabolic effects on electrolytes, carbohydrate metabolism, and lipid metabolism. Diltiazem is an excellent antianginal agent. It has been shown in one study to decrease proteinuria as effectively as lisinopril, and it may have renal protective effects. The antihypertensive efficacy of diltiazem as monotherapy is equal to that of all other antihypertensive classes, and it is tolerated as well or better than most other antihypertensive drugs. Diltiazem is particularly indicated in patients with hypertension and concurrent angina pectoris, diabetes, hyperlipidemias, and, perhaps, chronic renal disease.