Is it pretty much just lowering DHT too much/relative to other hormones, like estradiol?

I'm wondering if sides from propecia could be countered by arimidex.

I.E., you lower DHT too much, E2 creeps up, so you whack that with a-dex. (arimidex basically does to E what fin does to DHT).

I always wondered why propecia can potentially cause erectile dysfunction. ED is typically associated with poor vascularity. Why would propecia cause ED?...

NG2GB, I think that would be an effect of an altered adrogenic hormone balance.

DHT is a highly andregenic metabolite of testosterone and is responsible, in part, for sex drive, etc...

This is why some men need testosterone replacement to fix sex drive/ED issues.

DHT is also naturally suppressive of estrogens in a male. By lowering it, you open the door to increased estrogen. This is (probably) why other side effects include gynecomastia, etc...