Combination antihypertensive therapy with terazosin and other antihypertensive agents: results of clinical trials.

Clinical trials in which the selective alpha 1-adrenergic receptor blocker terazosin was given in combination with other antihypertensive agents are reviewed. Results of a recent study examining the effects of combination terazosin and verapamil therapy on blood pressure and heart rate are also presented. In several studies of the combination of terazosin plus a diuretic (hydrochlorothiazide, methyclothiazide, chlorthalidone, furosemide, amiloride, triamterene, metolazone, or spironolactone), significant decreases in one or more of the blood pressure variables studied were demonstrated (compared with diuretic plus placebo). In a placebo-controlled, double-blind study of terazosin plus atenolol, supine and standing blood pressures decreased significantly from baseline (atenolol monotherapy) after the addition of terazosin but not placebo. In a study of terazosin added to background therapy (including beta-blockers, diuretics, methyldopa, clonidine, captopril, guanethidine, hydralazine, and nifedipine), the addition of terazosin resulted in significant decreases in supine and standing diastolic blood pressures compared with baseline values (background therapy alone). Combination antihypertensive therapy with terazosin and verapamil reduced blood pressure to a significantly greater extent than either agent alone. Preliminary pharmacokinetic results indicate that terazosin did not alter the metabolism of verapamil. No significant abnormal laboratory test results have been reported for patients taking terazosin in combination with other antihypertensive agents; in fact some evidence suggests that terazosin may attenuate adverse lipid, glucose, and potassium changes associated with thiazide diuretics. Adverse experiences associated with terazosin combination therapy are usually mild to moderate. Results from all these studies suggest that terazosin effectively controls mild-to-moderate hypertension when it is used in combination with other antihypertensive agents without cumulative adverse effects.

RCT Entities:   Population Interventions Outcomes