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My dog has hives, Benadryl isn't helping. Should I go to ER?

Updated On September 23rd, 2025

Pet's info: Dog | American Staffordshire Terrier | Male | neutered | 1 year and 7 months old | 55 lbs

My dog has hives on his face and legs. I gave him Benadryl which doesn’t seem to be helping. His pulse is 140 bpm. Breathing 20 breathes per minute. His breathing is heavy but he often snore ms so it’s hard to tell if it’s just snoring or labored breathing. I’m wondering if I should take him to the emergency room or wait it out.

3 Answers

Most Helpful Answer

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Answered By David Elbeze, DVM, MRCVS

Veterinarian

Published on December 21st, 2018

This is probably an allergic reaction due to an insect bite or a plant outside. those reactions tend to resolve within 48 hours without treatment. if the swelling becomes too large or if your dog becomes lethargic, take him to the vet in order to get an antihistamine/steroid injection. from your description at this moment i think he is probably fine, but this can change so monitor him closely.

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    Answered By David Elbeze, DVM, MRCVS

    Veterinarian

    Published on November 5th, 2016

    It could be something he ingests, could be his food or treats. It could also be due to insects or something else in his environment. Benadryl tablets can usually help with this type of allergic reaction, so make sure you always have some at home.

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    Answered By Andrea M. Brodie, DVM

    Veterinarian

    Published on December 10th, 2016

    Food allergy is a possibility, but there could also be mites in the kibble (if you feed dry food) she may be allergic to, or a new room spray, laundry detergent or a bite from an insect. Watch her closely for breathing problems and if those occur she needs to be seen by a vet right away. You can feed her some boiled rice and chicken ,for a day or two. Then feed her regular food again. If she develops more hives after eating her regular food, you know that she is allergic to it, and you may have to change her food. Inspect her kibble to see whether it or something in it is moving. If so, throw it away.

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