Red bull is shit. Caffeine makes my dick hide. It literally makes my dick shrivel up to like 1.5 inches. Caffeine is shit and feels totally dirty when your on it. I won't drink anything caffeinated anymore because of the shitty dirty feelings it gives you. It makes me piss alot too and my dick fucking hates the bastard caffeine! Opiates fucking rock for sex, i can go for fucking like an hour or more if i need to and my dick stays nice and fucking hard.