Effects of an alpha 1-adrenergic blocker (prazosin HCl) on micturition disturbances associated with benign prostatic hypertrophy.

The effects of prazosin HCl treatment on several variables were determined in 16 patients suffering from micturition disturbances associated with benign prostatic hypertrophy. After administration of the drug in doses of 1-2 mg/day, subjective symptoms improved in 11 patients (68.8%). Urine retention rate, maximum urine flow rate, and average urine flow rate exhibited statistically significant improvement, but voided urine volume did not. Urethral pressures declined significantly in the bladder neck and prostatic urethra but not in the pressure at the external sphincter. The results suggest prazosin HCl may be effective in small doses in symptomatic treatment of benign prostatic hypertrophy.