A 40-year-old member asked:
How much time does it take for benadryl (diphenhydramine) to wear off?
1 doctor answer • 1 doctor weighed in

A Verified Doctoranswered
A US doctor answeredLearn more
Benadryl (diphenhydramine): Is usually active in your system for about 4 hours
4.1k viewsAnswered >2 years ago
Similar questions
A 32-year-old member asked:
How long does it take for liquid Benadryl (diphenhydramine) to wear off?
1 doctor answer • 2 doctors weighed in

Dr. Jeffrey Rumbyrtanswered
Allergy and Immunology 33 years experience
4-6 hours: Typically, the effect of Benadryl (diphenhydramine) is 4-6 hours. It may be longer in people with liver disease.
4.9k viewsReviewed >2 years ago
Tallassee, AL
A 39-year-old female asked:
Can I take 4 benadryl (diphenhydramine) at one time?
1 doctor answer • 2 doctors weighed in

Dr. Matt Wachsmananswered
Internal Medicine 37 years experience
Not recommended: that is above the usual dose and will likely produce significant sleepiness. Even one might be a problem with driving. Furthermore, it is very unlikely to produce more benefit than the recommended dose (1, at most 2).
2.1k viewsReviewed >2 years ago
A 34-year-old member asked:
What happens if you take too much benadryl (diphenhydramine)?
1 doctor answer • 2 doctors weighed in

Dr. Stevan Cordasanswered
Internal Medicine 58 years experience
5.7k viewsReviewed >2 years ago
Modesto, CA
A 31-year-old female asked:
How many Benadryl (diphenhydramine) pills can I take at one time?
1 doctor answer • 4 doctors weighed in

Dr. Alvin Linanswered
Geriatrics 31 years experience
Read label: You can take as many pills as directed by label as often as directed by label. Do not attempt to exceed amount or frequency. Be aware that even over-the-counter medications (and dietary supplements) can interact & even interfere w/prescription medications. So always tell your family physician (and other doctors) everything that you're taking whether prescribed or not.
5.3k viewsReviewed >2 years ago
CA
A 36-year-old member asked:
How much Benadryl (diphenhydramine) is considered too much?
2 doctor answers • 4 doctors weighed in

Dr. Steven Machtingeranswered
Allergy and Immunology 45 years experience
1 mg per 2 pounds: For children the correct dose is 1 mg/kg ( a kilogram is 2.2 pounds) every six hours as needed. Adults usually take 25-50 mg per dose. If you or your child need more than that you should consult your physician for advice. There are other drugs that are equally effective but cause less or no sedation and have fewer side-effects than Diphenhydramine (benadryl).
6.3k viewsReviewed >2 years ago
Last updated May 22, 2014
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