Finasteride

Finasteride (brand names Proscar and Propecia by Merck, among other generic names) is a synthetic drug approved by the FDA for the treatment of benign prostatic hyperplasia (BPH) and male pattern baldness (MPB). It is a type II 5α-reductase inhibitor. 5α-reductase is an enzyme that converts testosterone to dihydrotestosterone (DHT).