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A member asked:
I have once fainted after having a red bull. maybe i'm allergic or sensitive to caffeine. what are your thoughts?
A doctor has provided 1 answer
Unlikely allergy: Caffeine will not cause allergic reactions, but does have common side effects that are worse with higher doses as may be found in some "energy drinks." typical symptoms would be rapid heart rate, tremor, palpitations, GI upset and headache. Fainting is from lack of sufficient blood flow to the brain, which can be caused rarely by heart issues. Avoid high doses of caffeine until seen by doctor.
Answered 12/13/2015
5.3k views
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