Dutasteride is a 5-alpha reductase inhibitor. It reduces Dihydrotestosterone (DHT) levels by inhibiting the conversion of Testosterone into DHT. It's been shown to be highly effective in combatting Androgenic Alopecia. It does not reduce Testosterone levels, infact it usually increases them.

Dutagen is the brand name for Ranbaxy's Dutasteride pills and can be safely mixed and matched with any other brand of Dutasteride pills.