Terazosin in the treatment of benign prostatic hyperplasia. Terazosin Benign Prostatic Hyperplasia Study Group

To evaluate the efficacy and tolerability of terazosin, a long-acting selective alpha 1-receptor antagonist, in patients with benign prostatic hyperplasia.

Randomized, double-blind, multicenter (eight government and private facilities), placebo-controlled study.

Men aged 45 years or older, with qualifying signs and symptoms of benign prostatic hyperplasia (n = 160).

Terazosin or placebo once daily, with terazosin dosage titrated to the patient's response. After a 4-week placebo lead-in, 1 to 10 mg of terazosin or placebo was administered for 24 weeks.

Decreases in mean Boyarsky scores for obstructive and irritative symptoms and total scores and increases in peak urine flow rate.

Terazosin-treated patients had decreases in Boyarsky obstructive, irritative, and total scores of 3.3 (52%), 1.3 (29%), and 4.6 (42%), respectively, compared with decreases of 0.7 (12%), 0.4 (9%), and 1.1 (11%), respectively, in the placebo group (P < .05). Peak urine flow increased by a mean of 2.6 mL/s (30%) in terazosin-treated patients and 1.2 mL/s (14%) in placebo-treated patients (P < or = .05). Adverse events that differed significantly in the two groups were dizziness (19% in the terazosin group vs 5% in the placebo group) and urinary tract infection (1% in the terazosin group vs 10% in the placebo group).

These results suggest that terazosin given once daily in doses up to 10 mg alleviates symptoms and improves peak urine flow rate in men with benign prostatic hyperplasia and has an acceptable adverse event profile.