The role of combination therapy in the treatment of hypertension.

Only approximately 40% to 50% of hypertensive patients will achieve goal blood pressures of <140/ 90 mm Hg with monotherapy, regardless of the medication used. Fixed-dose combination therapy with two different classes of antihypertensive agents will achieve goal pressures in more than 70%. The sixth Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure has suggested that the use of combination therapy is appropriate as initial treatment. The advantages of combinations include: 1) greater blood pressure decrease and response rates than monotherapy; 2) fewer side effects with small doses of two drugs than with large doses of one agent; 3) improved adherence to treatment; and 4) possibly lower cost of therapy. Many different combinations of diuretics and beta-blockers, angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor antagonists, as well as ACE inhibitors and calcium antagonists are available. Two of these, Ziac and Capozide, have been approved as initial therapy. It is possible that the number of hypertensive individuals controlled at goal blood pressure levels will be increased if combination therapy is used as initial treatment.