3 doctors weighed in:
How quickly does Benadryl (diphenhydramine) start to work?
3 doctors weighed in

Dr. Giana Nicoara
Internal Medicine - Allergy & Immunology
1 doctor agrees
In brief: About 30 minutes
Lasts in the body for about 4-6 hours and then it needs to be redosed.

In brief: About 30 minutes
Lasts in the body for about 4-6 hours and then it needs to be redosed.
Dr. Giana Nicoara
Dr. Giana Nicoara
Thank
Dr. Jack Mutnick
Internal Medicine - Allergy & Immunology
In brief: Benadryl (diphenhydramine)
Onset of action is usually between 20-60 minutes.

In brief: Benadryl (diphenhydramine)
Onset of action is usually between 20-60 minutes.
Dr. Jack Mutnick
Dr. Jack Mutnick
Thank
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