Rogaine is more effective if the patient's hair loss has been ongoing for less than five years. Propecia, on the other hand, includes orally-active Finasteride, which was first used to treat prostate enlargement in 1992 (the evident trend here is that these medications were not initially meant to cure hair loss). Both products work by stopping the body from producing any more hair cells. However, only Rogaine will actually grow new hair cells where they are needed most - in its active ingredient, Minoxidil, you'll find a product that has been proven to promote new hair growth when applied to bald spots or areas of thinning hair. Finasteride works by blocking the action of an enzyme called 5-alpha reductase, which is necessary for male pattern hair loss as well as breast and testicular cancer. It should be noted that while both products are effective at preventing further hair loss, only Rogaine will help those patients who are already losing their hair. Using either product alone will not cause any new hair to grow. They must be used together with regular applications of Minoxidil or finasteride will not be effective at preventing more hair loss. Some studies have shown that patients who use both products together experience faster results than those who use one or the other alone. However, there is no proof that combining the two drugs will give any additional benefits over using them separately.