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My dog suddenly has big bumps on her head. Is it an allergic reaction?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Small (up to 22lb) | Female | unspayed | 18 lbs

My dog has massive bumps on her head that appeared rapidly, they're quite large bumps. Please help

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2 Answers

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Answered By Vanessa Yeager DVM MPH

Veterinarian

Published on October 17th, 2017

Hi and thanks for your post on Petco Pet Education Center, formerly Petcoach. Oh dear, this sounds like Bella has hives indicating an allergic reactions to something she was exposed to. Please take her into a veterinarian right away for treatment. She will need antihistamines and a steroid. Whatever she was exposed to needs to be identified so she does not have a reaction like this again. Best of luck!

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    Answered By Oneal Bogan, DVM

    Veterinarian

    Published on October 14th, 2017

    Hello. It looks like Bella is having an allergic reaction to something, possibly the shampoo that with used during her last treatment. You can try giving her 10 mg of Benadryl to ease the reaction, and I would bathe her in oatmeal shampoo to calm her skin. If this does not solve the problem, have your vet check her because she may need stronger medications to help her feel better.

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