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What causes black scabs and sores with fur loss on my dog's skin?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed Large (61lb +) | Female | unspayed | 1 year and 5 months old

Hi my dog has cone up with some sores on her back, near her leg and ear (see attached) do to u have some ideas as to what this could be? The one on her back, the fur has come away, and there is a black scab around the edge of it. She is not in any pain and is up to date with flea treatment. Thanks

3 Answers

Most Helpful Answer

Answered By Dr. Elizabeth

Veterinarian

Published on November 18th, 2017

Daisy may be having an allergic reaction. Allergies can be to contact with a substance, fleas, food or environmental. Sometimes dogs can get a random infection. I would search her closely for fleas. Topical flea products can still allow fleas to live long enough to cause a reaction. Oral flea products are much better because the fleas die faster.
Otherwise, I would take her into the vet for treatment (since it sounds like she has many lesions). Likely these are bacterial in nature but they are circular so ringworm (which humans can get) is always a potential. Once treatment is completed, watch Daisy for reoccurrence. If it comes back, then you start looking more closely at allergies. I hope this helps.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Jennifer Summerfield, DVM CPDT-KA
Veterinarian, Certified Dog Trainer
Published on February 18th, 2017
Poor Daisy! Flea bites can cause a lot of skin irritation in some dogs, especially if they have flea allergies. It's good that you've treated Daisy to get rid of the fleas. If the irritation is fairly minor, it should resolve on its own over the next few days now that the fleas are gone - you can try bathing her in aloe and oatmeal dog shampoo to help soothe her skin in the meantime.

If her skin is not getting any better in the next 5-7 days, or if she seems excessively itchy or painful with lots of scabs and hair loss, it would be best to take her to the vet for an exam - many dogs with this problem require prescription medication such a short-term oral steroid and an antibiotic to treat it effectively.
1Pet Parents found this answer helpful
Answered By Dr. Elizabeth
Veterinarian
Published on November 7th, 2019
Poor Daisy! It sounds like she is comfortable. Daisy needs to be examined by the veterinarian. Those spots could be several things including allergies, skin mites, flea bites (if she is allergic to flea bites, it only takes 1-2 fleas to cause this reaction), ringworm (which humans can get), hyperthyroidism or a bacterial infection.

The veterinarian will examined her to get a better idea of what is going on and then may prescribe medications to help treat the condition and make her feel better.

You can also add in an omega 3 fatty acid supplement for pets, this can help improve the skin health. Protect the areas from licking or scratching and she may need to wear and Elizabethan collar at all times.

Best of luck and please feel free to post any additional questions.
1Pet Parents found this answer helpful

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