Finasteride 1 mg, now marketed for alopecia androgenica.

Finasteride inhibits the conversion of testosterone to dihydrotestosterone, the androgen responsible for induction of sexual hair growth. But there are as yet no studies on the use of this drug in transsexuals

Finasteride is an androgen conversion inhibitor. Inhibits the production of dihydrotestosterone (DHT) from testosterone by inhibiting the binding of 5a-reductase, which is the enzyme responsible for converting testosterone to DHT. DHT is the active androgen found in the skin and prostate gland, and is associated with the development of male pattern baldness, excess body hair, and benign prostatic hypertrophy. Not suitable as a general anti-androgen since it only affects DHT production. However, it seems to be more helpful in counteracting male-pattern baldness and excess body hair than general anti-androgens.