2 doctors weighed in:
How long does it take for Benadryl (diphenhydramine) to make you drowsy?
2 doctors weighed in

1 doctor agrees
In brief: About 45 minutes
Benadryl (diphenhydramine) can make some people drowsy.
The maximum effect occurs in about 45 minutes or so. However, it can result in hyperalertness in some people.

In brief: About 45 minutes
Benadryl (diphenhydramine) can make some people drowsy.
The maximum effect occurs in about 45 minutes or so. However, it can result in hyperalertness in some people.
Dr. Tammi Schlichtemeier
Dr. Tammi Schlichtemeier
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