Lol, yeah, anyone with low caffeine intake REALLY feels a lot when they drink an energy drink, lol. Man, I had a starbucks Venti sized Bold Pick of the Day coffee a while back, and those things have a LOT of caffeine. I haven't had the money to drink energy drinks lately, but I still drink coke all the time, so it's not like I've got no caffeine intake, but that was unbelievable. It apparently has about 400 mg of caffeine in it.... I was on the verge of having the shakes, lol. Coming from someone used to drinking energy drinks and pretty much not feeling a thing, that was a VERY big surprise.