Finasteride stops testoserone from being converted into dihydrotestostorone (a more powerful compound). Most of the free testostorone in your body is dihydrotestosterone. It is responsible for the majority of lean muscle gains, however dihydrotestostorone, in some individuals will also cause prostate enlargement and hairloss.
Finasteride works by preventing your body from making dihydrotestosterone. In most cases reducing it as much as 75%. This can clearly cause gynecomastia, weak libido, limp , in some cases shrinkage....
It's a really nasty drug. For more info look at medical forums like webmd. Read how users are rating this drug and how many are getting horrible effects like permanent gynecomastia reduced libido, and permanent ED
The problem is nearly everyone whose used this drug get these problems. Once they are gotten they rarely go away. Ever.
Propecia gives you your hair at the cost of your manhood. My advice is to just go bald like nature intended and quit that vile drug. Hopefully you've quit in time and the gynecomastia can still be reversed and it hasn't ED
with your yet.....
I'm amazed that this drug is actually legal, while not deadly, it has some of the worst and most frequent side effects (especially for a bodybuilder) of any I can think of.