6 hours if not longe: The drowsiness effect from Benadryl (diphenhydramine) varies from one person to another. Although the antihistaminic effect may last for over a day, the drowsiness effect is likely less than 6 hrs. Alcohol just makes the drowsiness worse.
Answered 2/9/2021
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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