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What is the safe and correct Benadryl dosage for my 50-pound dog?

Updated on September 23rd, 2025

Pet's info: Dog | Pit Bull Terrier | Female | spayed | 7 months and 7 days old | 48 lbs

How much Benadryl do you give a 50lb dog

4 Answers

Most Helpful Answer

Answered By Destini R. Holloway, DVM

Veterinarian

Published on July 24th, 2017

The dosage is 1 mg per lb, so a 50 lb dog would get 50mg of Benadryl once every 12 hrs. Only pets with no hx of underlying heart disease or drug interactions can safely have Benadryl. You should always check with your vet on if this medication is appropriate for your pet, based on her history. Best wishes and take care.

5Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Dr. Strydom, DVM
Veterinarian
Published on December 23rd, 2019
The dose of Benadryl is 1mg per pound of body weight. If he is 20 pounds he needs about 20mg of Bendaryl. One adult capsule is 25mg so he can have that.

If all you have is liquid you will have to give him quite a bit. The liquid is only 2.5mg/ml so he will need 10ml which equals 2 teaspoons.
5Pet Parents found this answer helpful
Answered By Jennifer Summerfield, DVM CPDT-KA
Veterinarian, Certified Dog Trainer
Published on August 29th, 2020
It's a bit easier if you think of the dose as being 1 mg per pound of body weight. :) For my clients, I usually recommend rounding down to the nearest whole tablet size from there. So for a 71 pound dog, I would generally suggest giving 50 mg (which would be two 25 mg tablets).
1Pet Parents found this answer helpful
Answered By Jenna Beyer, DVM, MBA, cVMA
Veterinarian, Certified Veterinary Acupuncturist
Published on June 30th, 2018
This is the same medication as Benadryl. Here is info on using it in dogs: https://www.petcoach.co/canigive/dog/benadryl/

Personally, I don’t think that Benadryl is very effective for dog allergies. If you are concerned about allergies in Mylee, I would discuss other medications with your vet.

According to the article, she would need 5mg, or 1/5 of one of these tablets.
1Pet Parents found this answer helpful

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