Propecia dht blocker is a medicine for stopping hair loss in men and treating prostate adenoma. It slows down the conversion of testosterone to dihydrotestosterone by binding to the second-type 5-alpha reductase enzyme. Affects the root cause of baldness, but does not stimulate the growth of new hair, so it is used in conjunction with minoxidil. Holds existing hair and slows further baldness. The drug is available in pill form and is taken orally every day.