However the mechanism of action is not known. We do know it does not affect the levels of DHT, which is how Propecia works. Yes, it is much more effective. Minoxidil is dose-dependent. The higher the dose of minoxidil, the better the results.
Topical minoxidil has an excellent safety record.
The most common side effects are itching and skin irritation of the treated scalp. Unwanted hair growth may occur in areas adjacent to treatment sites, which can be little distressing to women when the face is involved. There were no clinically significant systemic side effects as compared to placebo. There has been numerous studies showing minoxidil causes clinically significant hair growth in both men and women. Minoxidil works best in the vertex area, but I have had several patients who have obtained hair growth in the front part of the scalp.