@Fletterby
I dated a guy who took medication for back pain. Not sure what the hell he was taking, but he'd take it every single morning ... and within 10 minutes the dude would have a painfully raging boner pitching a tent. He said it was a side effect of the meds.
Good luck on the hair loss. I lost that battle half a decade ago. I just shave bald now ... or wear a wig / hat, but mostly just shave bald and show off my manly chrome dome. Chicks dig owning your own baldness, and the wife tells me it makes me look like a badass action hero.