1 doctor weighed in:

How long does caffeine stay in your system?

1 doctor weighed in
Dr. Alan Wartenberg
Addiction Medicine

In brief: Variable

In general, it is short-acting, with a half-life of about 3 hours, but there may be genetic differences as well as drug/drug and drug/food interactions.
Some people are very sensitive to some effects of caffeine, and consuming some in the morning may even interfere with sleep. Drugs like caffeine alter the receptor/neurotransmitter environment, and those effects may last longer than the drug.

In brief: Variable

In general, it is short-acting, with a half-life of about 3 hours, but there may be genetic differences as well as drug/drug and drug/food interactions.
Some people are very sensitive to some effects of caffeine, and consuming some in the morning may even interfere with sleep. Drugs like caffeine alter the receptor/neurotransmitter environment, and those effects may last longer than the drug.
Dr. Alan Wartenberg
Dr. Alan Wartenberg
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