Caffeine drinks

[Maz]

Went out today to do a fast 12 miler and nearly half way around I took a decent swig of a High5 caffeine drink, within 15 seconds I felt ill and had to stop and be sick, I felt good when setting off but now feel a little ill, all the other tabs I use dont seem to have this effect...........wont be using those again

Excuse my ignorance, but why do they put caffeine in these drinks?
Is it meant to be an energy drink?

 

[PaulB]

Even the slightest trace of caffeine produces a mad firework-display migraine for me so I can't ever go near it again. I hate it when substances like that, whey and monosodium glutamate (E621) are so casually thrown into so many products often only to be discovered by the firework display when they have gone unheralded.

 

[classic33]

Best just to stick with gin and tonic during the ride.

That last one was for cows milk