It's surprisingly easy to overdose on caffeine, regardless of if you kill yourself though. I ended up in the hospital worried about strange heart palpitations once. It was due to too much caffeine. Apparently a litre and a half of pepsi plus a bag of chocolate covered espresso beans is a bad idea.
More likely, you'd be unable to consume the caffeine in a such a diluted form fast enough to exceed the rate at which the liver clears it - it takes time to empty out the stomach of all that water you're consuming along with it. Remember that humans detoxify caffeine much faster than most other mammals, too.
At a guess, you'd die from throwing your electrolyte balance off. Just like how drinking too much water can kill you. (Particularly if you drink while sweating - this routinely happens in marathons.)
Drinking even a tiny fraction of that much caffeine sounds awful. Caffeine has a terrible body load, and I'm pretty sure I'd want to die after three Red Bulls let alone 150. Coca tea is 1000x better, and they even sell it on Amazon:
Does it? The amount of active ingrdient in your normal coca leaf (which is all tea is) is miniscule - you need hundreds of pounds to make a gram of cocaine. You could suck back 100 bags of tea and soak them all you want and not even come close to getting "high" - you'd just be awake - coffee or regular caffeine-containing tea is more dangerous than that stuff.
"you need hundreds of pounds to make a gram of cocaine"
I think it's actually 125 grams of leaf makes one gram of cocaine. And a cup of coca tea is like 8% of a dose of cocaine, though it gets absorbed about twice as slow. So it's actually really not that much different than doing cocaine, in that the difference in dosage is only an order of magnitude, although somehow the difference is enough to make the tea completely safe and harmless as long as it isn't abused.
Smallgen, are you a member of heatsync labs or something? I was over there a couple of days ago and we randomly stumbled across this when trying to find out how much Africola somebody could drink without dying.
Nope, I actually just googled how much caffeine was in a couple of energy drinks today and I came upon that site and the death by caffeine calculator and thought it was worth sharing.
These things usually vary by region or country. For example, in Canada, they only very recently (or will be soon, I can't recall for sure) lifted restrictions on caffeine in non-colas. Previously, things like Mountain Dew, Sprite, 7-up, etc., could not contain caffeine.
That being said, I bet almost everyone here has felt the effects of caffeine intoxication before (http://en.wikipedia.org/wiki/Caffeine#Caffeine_intoxication). It's pretty easy to hit a level which causes those kind of symptoms.