Smooth Groove sure does know a lot about Propercia/balding...
and he's never posting his picture either...

They mentioned it a lot while teaching Endicrinology and again in Dermatology. It's one of the most common hormonal therapies. The funny thing is that Propecia was initially used to treat enlarged prostates.
If you're already starting to go bald at twenty, there really isn't any hope.
Not true. Propecia has been a savior for many young balding men. The only problem is most guys don't know about it until it's too late. Follicles are beyond repair in 3-5 years after their initial shrinkages and hair loss.
I know many that men have had positive results with Propecia. But not all. And how many of those men already started going bald at 20?
Just because someone starts losing hair earlier, it doesn't mean that he'll lose more hair. The timing and amount of hair loss all depend on the person's genetic makeup.
As far as I know, Propecia is far more effective at retaining current hair then regrowing hair. But the earlier a patient starts on the drug, the higher his chances of regrowth are.
Of course, each patient's response to Propecia is also dependent on his genes.