Propecia a good idea? Depends on you, really...
I think for most people finasteride is reasonably safe and well-tolerated.
It would appear that most people experience some hair growth for up to two years, and then slowly lose hair from that point onward. However, people who are not on Propecia continue to lose hair over the same period, and at a higher rate, so even if the benefits of Propecia diminish, you will likely be better off than someonw who never took Propecia, at least when it comes to your hair.
There may be a number of reasons why Propecia does not allow one to regrow hair and maintain it indefinitely. One of the simplest reasons is that DHT is not the only androgenic hormone in the body (though it is the most potent), and other androgens can promote the hair loss process, albeit more slowly than DHT can. Also, Propecia does not completely eliminate DHT production, anyway; in fact, there is more type-I 5AR in the skin than type-II, so it's kind of suprising that Propecia works as well as it does. One reason may be that the dermal papilla cells express type-II 5AR, but I think it's likely that serum DHT is as important if not more important to the development of the hair follicle than DHT produced in situ. Dr. Lee himself has said that he doubts finasteride would be a good topical agent for hairloss, since it wouldn't inhibit much of the production of DHT there (he went on to suggest dutasteride ought to work well topically, because of its dual inhibition of types-I and II 5AR).
As an aside, it's interesting to ponder the implications of this assertion. By Dr. Lee's logic, finasteride shouldn't work systemically, either, if the skin production of DHT is what counts. In my oppinion, he undermines his own claims about the efficacy of his Xandrox products with this line of reasoning: Serum DHT must be important, or Propecia would be ineffective either sytemically or topically, and hence topical 5AR inhibitors which act only in the skin would likely be ineffective, since they do not protect against serum DHT. I also found the statements of Dr. Alex Khadavi (CEO of Revivogen) very interesting...see the following link:
http://www.regrowth.com/hair_loss_treat ... erview.cfm
Dr. Khadavi claims that his home-made topical finasteride was effective. As I said above, Dr. Lee has predicted topical finasteride would be of relatively little value. Both can't be right. I suspect Dr. Lee is more correct than Dr. Khadavi for one simple reason: If topical finasteride acted only at the site of administration, it probably would not be very effective. However, finasteride has a fairly typical steroid structure; most chemicals with similar structure are readily absorbed through the skin (e.g. testoserone creams and progesterone/estrogen transdermal delivery patches). My guess is that if Dr. Khadavi is telling the truth about his topical finasteride's efficacy, he has very little understanding of transdermal pharmacology, since what he likely created was a transdermal delivery system that allowed for whole-body effects; in other words, no better or worse than oral finasteride. Dr. Lee, on the other hand, seems to be conflicted about the importance of serum DHT and DHT produced only in the skin. He can't have it both ways: Either serum DHT is important, and topical azelaic acid is not likely to be useful, or serum DHT is unimportant, and thus finasteride shouldn't work due to its weak effects in the skin.
Anway, back to the safety of Propecia: Your only recourse is to try it and see. The odds are in your favor that you will tolerate it well, and that it will at least stave off the loss of hair for many years. Plus, unlike the purported antiandrogenic products of Dr. Lee and Revivogen, Propecia has been subjected to extensive clinical trials that have proven its efficacy for male pattern baldness. Given the reasoning of these Dr.'s of alternative male pattern baldness therapies, I'm not so sure I'd trust their professional judgement. You can trust the FDA to a much greater extent (though they're far from perfect).
Now, I am one of the few people who has had a very bad reaction to Propecia, much to my dismay. I got severly depressed on it, worse with each attempt, before I finally gave up on it. Some people experience groin aches, impotence, irritability, moodiness, soft erections, development of man-boobs (gynecomastia), and a bunch of other problems. I think their stories are likely to be quite real, and while relatively rare, severe adverse effects are a possibility. If you have them, get off the drug, the sooner the better for your own quality of life. Systemic inhibition of 5AR does more to your body than make it grow hair in the right places. It interferes with the metabolism of several steroid hormones in your body, including corticosteroids (stress hormones) and progesterone; the metabolites of these are so-called neurostearoids, which are critical enhancers of the neurotransmitter GABA at its type A receptor. In other words, finasteride has an impact on how your brain works, both in its anti-androgen effects, as well as through other mechanisms that you hear little about unless you dig. Nobody knows how important such alterations really are. The evidence is that most people tolerate the changes well. This is the best information you or anyone else has to go on, currently. But, be aware that there are things we don't know, and what you don't know could definitely still hurt you. Just be educated, know the cost-benefit ratio, and act accordingly.
