A multicenter, randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of terazosin in the treatment of benign prostatic hyperplasia.

Objectives: This study was designed to evaluate the safety and efficacy of the selective alpha 1-adrenoceptor blocker terazosin in the treatment of benign prostatic hyperplasia (BPH).

Methods: Two hundred twenty-four patients aged 50 to 80 years, who had a diagnosis of BPH based on medical history, physical examination, and digital palpation, were recruited from 11 different sites between January 1992 and January 1994. The study consisted of a screening phase, a placebo phase, a double-blind dose-titration phase, and a double-blind maintenance phase.

Results: Of the patients recruited, 164 entered the double-blind phase and of these 134 were evaluable. Only 11 patients withdrew because of an adverse event, 7 in the terazosin and 4 in the placebo group. Compared to placebo, terazosin significantly increased peak and mean urine flow rates without significantly affecting voided volume or postvoid residual volume. It significantly improved both the obstructive and irritative symptoms associated with BPH. Fifty-one patients from the terazosin group reported a total of 120 adverse events compared with 83 reported by 42 patients in the placebo group. The majority of these events were mild to moderate. Seventeen terazosin-treated patients reported hypotension-related adverse events and 4 withdrew from the study. However, concurrent treatment with antihypertensive agents did not affect the blood pressure response of the terazosin group.

Conclusions: Overall, this study showed terazosin to be safe and effective in relieving the signs and symptoms of BPH and should be considered as a treatment alternative.