Effects of finasteride on size of the prostate gland and semen quality in dogs with benign prostatic hypertrophy.
OBJECTIVE
To determine the effect of the 5alpha-reductase inhibitor finasteride on prostatic diameter and volume, semen quality, and serum dihydrotestosterone (DHT) and testosterone concentrations in dogs with spontaneous benign prostatic hypertrophy (BPH).


METHODS
Double-blind placebo-controlled trial.


METHODS
9 dogs with BPH.


METHODS
Five dogs were treated with finasteride for 16 weeks (0.1 to 0.5 mg/kg [0.05 to 0.23 mg/lb] of body weight, PO, q 24 h); the other 4 received a placebo. Prostatic diameter, measured radiographically, prostatic volume, measured ultrasonographically, semen quality, and serum DHT and testosterone concentrations were evaluated before and during treatment. After receiving the placebo for 16 weeks, the 4 control dogs were treated with finasteride for 16 weeks, and evaluations were repeated.


RESULTS
Finasteride significantly decreased prostatic diameter (mean percentage decrease, 20%), prostatic volume (mean percentage decrease, 43%), and serum DHT concentration (mean percentage decrease, 58%). Finasteride decreased semen volume but did not adversely effect semen quality or serum testosterone concentration. No adverse effects were reported by owners of dogs in the study.


CONCLUSIONS
Results suggest that finasteride can be used to reduce prostatic size in dogs with BPH without adversely affecting semen quality or serum testosterone concentration.
Sirinarumitr
K
K
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman 99164, USA.
Johnston
S D
SD
Kustritz
M V
MV
Johnston
G R
GR
Sarkar
D K
DK
Memon
M A
MA
D000818:Animals; D013196:Dihydrotestosterone / Q000097:blood; D004283:Dog Diseases / Q000175:diagnosis / Q000188:drug therapy*; D004285:Dogs; D004311:Double-Blind Method; D018120:Finasteride / Q000627:therapeutic use*; D008297:Male; D011467:Prostate / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011470:Prostatic Hyperplasia / Q000188:drug therapy / Q000662:veterinary*; D011859:Radiography; D012661:Semen / Q000187:drug effects; D013739:Testosterone / Q000097:blood; D014463:Ultrasonography
D013196:Dihydrotestosterone; D013739:Testosterone; D018120:Finasteride