Comparison of oral minoxidil, finasteride, and dutasteride for treating androgenetic alopecia.

The average plasma half-lives of minoxidil, finasteride, and dutasteride are ∼4 h, ∼4.5 h, and ∼5 weeks, respectively. Minoxidil acts through multiple pathways to promote hair growth. It has been shown as a vasodilator, an anti-inflammatory agent, a Wnt/β-catenin signaling inducer, and an antiandrogen. Finasteride inhibits 5α-reductase (5AR) type II isoenzyme, while dutasteride inhibits both type I and type II. Thus, dutasteride suppresses DHT levels more than finasteride in the serum and scalp.