If I were you I would definably discuss your plans with a urologist. This sounds very dangerous, to say the least. You said it yourself, an erection lasting more than 3 hours is dangerous, and immediate actions are to be taken when someone has a boner for that long. To do this on a regular basis??? I dunno about that... the risks seem to outweigh the benefits ... to me anyways ..
I also used to work in a retail pharmacy for 5 years, and we dispensed all kinds of shit for boners. Viagra, Cialis, and Levitra were of course were very common, but Caverject was up there, too. This is a prescription item now, mind you, so if you want it legally just find a doctor that will write you a script for it (I live in the US). Another thing, as I'm sure you know, caverject is a injection. It's a little autoinjector, and the medicine is administered into the glans penis. The only thing that sounds worse than that is Muse, which is a inter-urethral suppository. Muse is also used to get insta boners. Of course people don't want to use this shit, because obviously it sucks, unless your some kind of sadomasochist. They're usually used as a last resort, because Viagra and other vasodiolaters will interact with other medications, such as anti-arrhytHydromaxia medications.
The things people will do to get boners
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