[Arikana]

I don't see how it is. A few years ago, before I decided to stop drinking pop for the most part, (with the exception of Canada Dry's Ginger Ale), I would drink up to six to eight cans a day and the excess caffeine would make me even more tired. :| While I don't think it's common, I'm sure others also feel this...distinct side effect from consuming caffeine, particularly after having ingested large amounts.

That, and this: http://answers.yahoo.com/question/in...=1006050328884