Dr. Rassman, hi again.
I’m a long-time follower and fan of your blog. Besides enjoying the quality of the information you share, I really admire your realistic and down-to-earth approach when making comments about new treatments and current research. Some people consider your view to be pessimistic but I find it downright sincere. Thanks for the great job.
My question today refers to something I find in your comments quite often: the idea that even if someone has been on Propecia for quite a while, he will eventually lose the battle against hair loss. Now, assuming my understanding is correct, Propecia will keep DHT levels low for as long as the patient takes it, correct? If that’s a fact, why do we eventually “lose the battle”? Is it because the % of DHT that is not blocked by Propecia is enough to eventually affect the hair we retain or is it because besides DHT, there are other root causes still unknown to us?
Thanks a lot, Dr. Rassman!
Propecia generally impacts only 70% of the DHT by a process called competitive inhibition. This means that the drug competes with DHT at its receptor site. We really do not know much more about this competitive process, but we know that some people get great responses from the drug at the 1mg dose, while others do not. I think that the sensitivity of the receptors varies as the genetic process advances.
I have discussed apoptosis in the past, which is cell death, and this hits the hair follicles at the end of their lives. The drugs can not give back the life that the process takes away. Take a look at the various posts in the past that discuss apoptosis here.