If it gets absorbed systemically, I would expect so.
Local and Systemic Reduction by Topical Finasteride or Flutamide of Hamster Flank Organ Size and Enzyme Activity nature.com/jid/journal/v105/ … 0726a.html
The hamster flank organ is a widely used model of the control of sebaceous gland activity by androgens and anti-androgens. Finasteride, a 5alpha-reductase inhibitor, was administered locally on the surface of the right flank organ and right ear twice daily for 4 weeks. The treatment caused similar 12% to 30% reductions in the size of the sebaceous glands in both flank organs. Moreover, relative mRNA levels of the androgen-regulated FAR-17a gene measured by in situ hybridization as well as [3H]-thymidine incorporation and 5alpha-reductase activity were similarly decreased in the two flank organs after topical application. The pure anti-androgen flutamide, at the same doses, exerted a more potent effect on all the same parameters, and the effect was also comparable on both the treated and untreated sides of flank organs. Finasteride and flutamide significantly decreased ventral and dorsal prostatic weights after topical application . The present data show that the topical administration of finasteride, in analogy with flutamide, causes local inhibition of sebaceous gland growth in both the costovertebral organs and ears. However, as demonstrated by the similar inhibitory effect in the contralateral untreated side and the reduced weight of the dorsal and ventral lobes of the prostate and seminal vesicles, finasteride and flutamide both exert significant systemic effects.
Comparing the therapeutic effects of finasteride gel and tablet in treatment of the androgenetic alopeciaijdvl.com/article.asp?issn=0 … 51;aulast=
Background: Finasteride, a type P-selective 5a-reductase inhibitor, as a causative agent of decreasing dihydroxy testestrone (DHT) level, is effective in the treatment of male androgenic alopecia. Aim: We compared the local and oral finasteride in the treatment of androgenic alopecia. Method: This is a double blind, randomized clinical trial study of 45 male patients, who were referred with alopecia to the private clinics and departments in Boo-Ali Sina Hospital, in Sari. Patients with male androgenic alopecia were selected according to the history and physical examinations. The patients were randomly divided into two: topical finasteride (A) and oral finasteride (B) groups. Topical finasteride group (A) received a topical gel of 1% finasteride and placebo tablets, while the oral finasteride group (B) received finasteride tablets (1 mg) and gel base (without drug) as placebo for 6 months. The patients were followed by clinical observation and recording of side effects prior to the treatment and at the end of first week, and then by a monthly follow-up. The size of bald area, total hair count, and terminal hair were studied. Data were analyzed by descriptive and Chi-square statistical test. Results: The mean duration of hair loss was 18.8±23.10 months. Each month the terminal hair, size of bald area and hair count between the two groups were compared. There were no significant differences between the two groups as a viewpoint of hair thickness, hair counts and the size of bald area. Serial measurements indicated a significant increase in hair counts and terminal hair counts between the two groups. Conclusions: The results of this study showed that the therapeutic effects of both finasteride gel and finasteride tablet were relatively similar to each other.
