I own pure caffeine and make my own so yeah they do. I have a fre in my fridge that come in 300, 500, and 1K MG of caffeine with a 200 DV of B12 other than that they are just Monin syrup and club soda. But have one of the sissy sounding Rose and lavender flavored one (yes that is seriously their flavor) that come in 1K MG of caffeine and you will be effected have two and you may as well have just taken some speed.
I once downed 4 in about 5 hours. I punched a wall for no damn reason other than i feat like i was going mad I then ran 10 miles came back in went for a swim, fucked, went or another swim, tried to sleep and failed, wet to the bar, got wasted, fucked, went to my nest day of work, listened to concerned voice mails i neglected, talked about said emails, tried to sleep failed, then played WoW and TF2 till I was finally tired and it had been over 2 days since i last slept and passed out in my bed. Yeah not the best idea. But normal energy drinks have very little effect on me
I once downed 4 in about 5 hours. I punched a wall for no damn reason other than i feat like i was going mad I then ran 10 miles came back in went for a swim, fucked, went or another swim, tried to sleep and failed, wet to the bar, got wasted, fucked, went to my nest day of work, listened to concerned voice mails i neglected, talked about said emails, tried to sleep failed, then played WoW and TF2 till I was finally tired and it had been over 2 days since i last slept and passed out in my bed. Yeah not the best idea. But normal energy drinks have very little effect on me