7 doctors weighed in:

How long does caffeine stay in your system?

7 doctors weighed in
Dr. George Valdez
Family Medicine
6 doctors agree

In brief: Depends

Depends on size and age of the person, and what else is in the system, but the half life is 3 to 12 hours.

In brief: Depends

Depends on size and age of the person, and what else is in the system, but the half life is 3 to 12 hours.
Dr. George Valdez
Dr. George Valdez
Thank
Dr. Gregg Albers
Addiction Medicine
1 doctor agrees

In brief: Depends on dose

The more caffeine you drink, the higher the initial level.
After4-6 hours your level will drop. Some of us are more sensitive, and after one cup of coffee will have effects for more than 12 hours.

In brief: Depends on dose

The more caffeine you drink, the higher the initial level.
After4-6 hours your level will drop. Some of us are more sensitive, and after one cup of coffee will have effects for more than 12 hours.
Dr. Gregg Albers
Dr. Gregg Albers
Thank
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