This is not a troll message or something I want to get flamed for... it's a serious question.

I'm not sure that anyone has ever attempted this and am even more sure I wouldn't have the balls to (no pun intended).... but if one were to inject IGF or some other analogue in to their penis, would it, in theory, increase length/girth?

There is a medication out called Caverject that is given as a direct injection in to the penis that many have reported using to increase penis length/girth as a reaction to the prolonged erections it induces.

Both of these seems like plausible mechanisms to make a small penis bigger. I don't know why I thought about this tonight, I'm laughing just thinking about it. Does anyone think there is any merit here?

All I know is that I wouldn't want to be one of the early recipients of such a procedure; I'd hate to ruin my penis.

to OP How big (or small) is your **** that you are considering this? I have a pretty big **** and it hasn't benefitted me that much. Unless your tiny, it doesn't matter.

The only way to increase penile size is to increase the amount of cells within and thus it's volume. It must literally grow.

Whenever you modify any system within your body, you have to look at the effects, good and bad. Sure IGF-1 has some purported good effects. But...

"The IGF signaling pathway appears to play a crucial role in cancer. Several studies have shown that increased levels of IGF lead to an increased risk of cancer.[19] Studies done on lung cancer cells show that drugs inhibiting such signaling can be of potential interest in cancer therapy.[20]"

So maybe your penis will grow but not in the way that you want it.