Is it normal for caffeine to not have an effect?!

I don't think so. Same thing happens to me, it makes me sleep! LOL!


Anyway, check this out:


In the Loughborough study, published in the Human Psychopharmacology: Clinical and Experimental journal, 10 adults were studied to see what effect different drinks had on their wakefulness.

They had all volunteered to restrict their sleep to five hours on the day before participating in the trial.

An hour after eating a light lunch they were given either an energy drink containing 42g of sugar and 30 milligrams of caffeine, or an identically tasting zero-sugar drink.

They then performed a monotonous 90-minute test during the afternoon "dip" to assess their sleepiness and ability to concentrate.

The researchers found that for the first 30 minutes there was no difference in the reaction times or error rates.

But 50 minutes after consuming the drinks, the performance of those who had had the energy drink started to slip, and they became significantly sleepier.

BBC News

Could of been cheap coffee or you could have a tolerance built up. Or you were really tired. But its happens to me often also. Wake up, drink a gallon of Joe and you still feel like you need a nap. Sometimes I just pop a few caffeine pills instead

You sure it was caffeine free coca cola? I drink a lot of caffeine,and it has very little effect on me anymore.Maybe your body is more tolerant to caffeine than others.You may have been very tired as well.Who knows for sure,but this is the least of your worries I'm sure.Take care.

Caffeine affects different people in different.

I used to work with someone who was hyperactive and drank coffee to go to sleep.

It defers from person to person. Like alcohol, some get drunk after just a few beers, while others drink like 9 before they feel the effect.

Yeah definitely.