The effect of finasteride, a 5 alpha-reductase inhibitor, on scalp skin testosterone and dihydrotestosterone concentrations in patients with male pattern baldness.
The effects of the 5 alpha-reductase inhibitor, finasteride, on scalp skin testosterone (T) and dihydrotestosterone (DHT) levels were studied in patients with male pattern baldness. In a double blind study, male patients undergoing hair transplantation were treated with oral finasteride (5 mg/day) or placebo for 28 days. Scalp skin biopsies were obtained before and after treatment for measurement of T and DHT by high pressure liquid chromatography-RIA. In 10 male subjects studied at baseline, mean (+/- SEM) DHT levels were significantly higher in bald (7.37 +/- 1.24 pmol/g) compared to hair-containing (4.20 +/- 0.65 pmol/g) scalp, whereas there was no difference in mean T levels at baseline. In bald scalp from 8 patients treated with finasteride, the mean DHT concentration decreased from 6.40 +/- 1.07 pmol/g at baseline to 3.62 +/- 0.38 pmol/g on day 28. Scalp T levels increased in 6 of 8 subjects treated with finasteride. Finasteride decreased the mean serum DHT concentration from 1.36 +/- 0.18 nmol/L (n = 8) at baseline to 0.46 +/- 0.10 nmol/L on day 28 and had no effect on serum T. There were no significant changes in scalp or serum T or DHT in placebo-treated patients. In this study, male subjects treated with 5 mg/day finasteride for 4 weeks had significantly decreased concentrations of DHT in bald scalp, resulting in a mean level similar to the baseline levels found in hair-containing scalp.
Dallob
A L
AL
Merck Research Laboratories, Rahway, New Jersey 07065.
Sadick
N S
NS
Unger
W
W
Lipert
S
S
Geissler
L A
LA
Gregoire
S L
SL
Nguyen
H H
HH
Moore
E C
EC
Tanaka
W K
WK
D058891:5-alpha Reductase Inhibitors; D000328:Adult; D000505:Alopecia / Q000188:drug therapy* / Q000378:metabolism; D013196:Dihydrotestosterone / Q000097:blood / Q000378:metabolism*; D004311:Double-Blind Method; D018120:Finasteride / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012535:Scalp / Q000187:drug effects / Q000378:metabolism*; D013739:Testosterone / Q000097:blood / Q000378:metabolism*
D058891:5-alpha Reductase Inhibitors; D013196:Dihydrotestosterone; D013739:Testosterone; D018120:Finasteride