A 12-week placebo-controlled double-blind study of prazosin in the treatment of prostatic obstruction due to benign prostatic hyperplasia.
A series of 93 normotensive patients with benign prostatic hyperplasia and maximum urinary flow rates < 15 ml/s, treated at 2 hospital centres using an identical protocol, was randomly assigned to receive a 12-week course of treatment with prazosin or placebo in a double-blind parallel group trial. A total of 75 patients completed the study and were suitable for the final analysis. Prazosin was administered orally in doses of 0.5 mg and then 1 mg twice daily for 4 days and 2 mg twice daily for the remainder of the trial. Patients on treatment with prazosin exhibited a significantly increased maximum urinary flow rate as compared with placebo, with a significant reduction in maximum voiding detrusor pressure. Prazosin therapy did not produce a significant effect on either frequency or standard parameters of detrusor instability. A double-blind overall assessment of drug efficacy and tolerance significantly favoured prazosin therapy. A total of 30 patients receiving prazosin and 28 receiving placebo reported varied adverse effects. Eighteen patients were excluded from the final analysis, 10 being withdrawn because of adverse effects, 7 on treatment with prazosin and 3 in the placebo group. In long-term usage oral prazosin was well tolerated and appeared to improve obstructed voiding in patients with benign prostatic hyperplasia.
Chapple
C R
CR
Department of Urology, Middlesex Hospital, London.
Stott
M
M
Abrams
P H
PH
Christmas
T J
TJ
Milroy
E J
EJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D008875:Middle Aged; D011224:Prazosin / Q000627:therapeutic use*; D011470:Prostatic Hyperplasia / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D014521:Urethra / Q000503:physiopathology; D014554:Urination; D014555:Urination Disorders / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D014563:Urodynamics
D011224:Prazosin