2 doctors weighed in:

How long does it take for Benadryl (diphenhydramine) to leave the body?

2 doctors weighed in
Dr. Andrew Oswari
Family Medicine
1 doctor agrees

In brief: Half life is 8 hours

Its effectiveness only lasts 6-8 hours usually.
It's half life is 8 hours, so it may take up to 72 hours to leave your system completely.

In brief: Half life is 8 hours

Its effectiveness only lasts 6-8 hours usually.
It's half life is 8 hours, so it may take up to 72 hours to leave your system completely.
Dr. Andrew Oswari
Dr. Andrew Oswari
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