man I wish a red bull worked, I can drink 4 and the only thing I feel is my heart hurting (I don't drink Red Bull any more btw, that heart thing freaks me out)
Red bull is not the strongest energy drink at all. I need to chug 2 of the normal size cans in succession to feel anything at all. Monster and Rock Star are fantastic if you need to keep up physical work but I worry about their effect on my heart after reading about how bad they can be.