You have to understand why people lose hair that they gained with Rogaine. It's because the Dihydrotestosterone (DHT) is still there. DHT is a testosterone by-product and that plus a genetic vulnerability to DHT is what causes male pattern baldness. Removing DHT (i.e. removing the testicles) is almost always sufficient to stop DHT based hair loss.
Normal human hair loss is in the 100-150 hairs per day. The average human head (not affected by male pattern baldness) has 100,000 or more hairs on it.
Hairs go through three stages:
Anagen -- active hair growth that lasts between two to six years
Catagen -- transitional hair growth that lasts two to three weeks
Telogen -- resting phase that lasts about two to three months; at the end of the resting phase the hair is shed and a new hair replaces it and the growing cycle starts again.
Androgenic alopecia is the formal name for male pattern baldness. Basically what happens is that the Anagen phase becomes shorter and shorter and shorter while the Telogen phase becomes longer and longer and longer, all due to the impacts of DHT.
Rogaine (or generic Minoxidil, which is basically the same thing but far cheaper) encourages hair growth. Finasteride (marketed as Propecia when used for hair loss) blocks DHT formation to some degree. The less testosterone you have, the more effective finasteride will be since there will be less testosterone to even turn into DHT to begin with. Also, the less testosterone you have, the more likely minoxidil will be effective since it's less likely to have to fight against DHT.
However, if a region of the scalp has been under the effect of DHT for too long, the hairs in that region may actually die out and not return.
One thing that can be done as an alternative is to find a hair restoration surgeon who uses the new
ACell + PRP technique. ACell is a product originally designed to stimulate stem cells in a wound site to produce healthy tissue instead of scar tissue. Some hair restoration surgeons began using it to minimize scarring during hair transplants and discovered that it seemed to promote new hair growth. Subsequent studies do seem to verify that it can promote new hair growth when applied via injections to the entire scalp, though as always, your mileage may vary.
I personally have very extensive male pattern baldness and do not expect transplants to be sufficient to give me a normal head of hair at the current time. But eventually I do plan to save the money for an ACell + PRP treatment and see if that can increase my overall hair growth and density to where transplants can do the rest.
