Finasteride prevents the conversion of testosterone to dihydrotestosterone (DHT) in the body. DHT is involved in the development of benign prostatic hyperplasia (BPH).
Finasteride (Propecia) is used to treat male pattern hair loss in men. Finasteride (Proscar) is used to treat symptoms of benign prostatic hyperplasia (BPH) in men with an enlarged prostate. 
 finasteride is for use in men only.
Finasteride may also be used for purposes not listed in this medication guide.
