A: The main studies by Merck looked at men between the ages of 18 and 41. The five year data (which, in my view, is most important) showed that 48% of men had an increase in hair growth and 42% had no change over baseline. Thus a full 90% held on to their hair or had more over a 5-year period. This compares very favorably to the placebo group where 75% lost hair over the 5-year period.

I think the most interesting question relates to the 10% who continued to lose hair in the treated group. Did these men lose hair at a slower rate than the non-treated group? Based on the action of finasteride on blocking DHT and DHT’s central role in causing male pattern hair loss, it is reasonable to assume that even these “non-responders” did have some benefit from the drug, albeit small. If half of those on the medication continued to lose hair did so at a rate slower than the placebo group, then 95% of patients actually benefited from the medication to some degree – an extraordinarily high success rate, in my opinion.

A: Hair transplants work because hair removed from the permanent zone in the back and sides of the scalp continues to grow when transplanted to the balding area in the front or top of one’s head. The reason is that the genetic predisposition for hair to fall out resides in the hair follicle itself, rather than in the scalp. This predisposition is an inherited sensitivity to the effects of DHT, which causes affected hair to decrease in diameter and in length and eventually disappear – a process called “miniaturization.” When DHT resistant hair from the back of the scalp is transplanted to the top, it will continue to be resistant to DHT in its new location and grow normally.

A: It is a bit too early to tell. My sense is that it will not have any practical long-term benefits for the treatment of hair loss (MPB), since it doesn’t get to the cause of androgenetic hair loss, i.e. DHT. Treatments such as copper-peptide, saw-palmetto, laser therapy, have all been promoted for male pattern hair loss, but have not really turned out to have any significant long-term benefits. Further studies need to be done on PRP to get a better sense of its value in combating hair loss.

On the other hand, PRP can have a significant impact on wound healing and it is possible that it may be useful in promoting healing after a hair transplant in both the donor and recipient areas of the scalp.

For further reading, see the Bernstein Medical – Center for Hair Restoration web page on Platelet Rich Plasma (PRP).

A: Hair loss is due to the action of DHT (a byproduct of testosterone) on hair follicles that cause them to shrink and eventually disappear (the process is called miniaturization). The follicles on the back and sides of the scalp are not sensitive to DHT and therefore don’t bald (miniaturize).

When you transplant hair from the back and sides to the bald area on the front or top of the scalp the hair follicles maintain their original characteristics (their resistance to DHT) and therefore they will continue to grow.

A: The only effective DHT blockers are finasteride (Propecia, Proscar) and dutasteride (Avodart).

These medications require a doctor’s prescription and are not sold OTC. Nizoral is a topical shampoo for seborrhea (a type of dandruff) that is sold over the counter, but it is not effective in treating hair loss.