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Why is my dog's coat bad with red, bald patches? How can I help her?

Updated On September 23rd, 2025

Hello I was wondering what would be the cause to this happening to my Dog she has had this over a little more than a month now, also what can I do to help her coat get better and help her.

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3 Answers

Most Helpful Answer

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Answered By Jessica Desrosiers

Veterinary Technician

Published on April 10th, 2024

Ouch! That looks like a severe allergy, infection, or even parasite infection that is causing the large patches of redness and baldness. It's best to bring your pup into your vet for treatment and care since it's gotten to a serious enough point that treatments at home likely won't do too much. Your vet can take a sample of the affected area to test for issues such as mites/fleas, bacteria, yeast, etc, or start you on some allergy medications or a food trial to see if that helps. In the meantime, it's best to keep an Elizabethan (cone) collar or T-shirt on your pup to keep her from licking or scratching the area as licking can lead to worsening of infection. Checking for any parasites such as fleas and ticks and treating your pup and her environment may also help. It's also a good idea to keep the area clean and dry. Since there are so many causes of this, it's best to see your vet to help narrow down what's happening and get your pup on the right path.

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Related Answers from Veterinarians

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    Answered By Kevin Sanada, DVM

    Veterinarian

    Published on August 5th, 2017

    There are many different reasons for bald spots, but considering your recent battle with fleas, there's a good chance it was due to that. The hair coat can sometimes look worse before it gets better, since the old damaged hair is falling out and the new hair is growing in. If the skin in the bald spot is not red or crusty, then it's likely healthy skin. You may also look closely to see if new hair is growing in - that's a good sign that all is well. If the skin is looking red and/or crusty, then it may be an infection. These can be caused by bacteria, fungus or mites. A veterinarian will be able to diagnose the cause through an exam and certain tests. I hope this helps and Sam gets his hair back soon.

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    Answered By Andrea M. Brodie, DVM

    Veterinarian

    Published on March 31st, 2018

    It is a well known side effect that can occur when using a spot on. As long as the skin does not turn an angry red, oozes or otherwise looks injured, you do not have to worry, Eventually the hair will regrow. There really is no way to avoid that. You may want to try another brand for cats next time.

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