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Why does my dog have black spots on her skin, especially on her leg?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Medium (23 - 60lb) | Female | spayed | 38 lbs

My dog has developed a few black spots on her skin on the back leg

2 Answers

Most Helpful Answer

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Answered By David Elbeze, DVM, MRCVS

Veterinarian

Published on November 2nd, 2017

This is probably caused by an allergic reaction. first of all make sure you de-flea Sandi regularly every month with a high quality spot on (ex. Advantage) as fleas are by far the most common reason for these reactions. If the fleas are not the problem, it could be an allergic reaction to food or an environmental factor. this is more complicated to treat and will sometimes require medications such as Steroids, anti histamines or cyclosporin in order to stop the allergy.

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    Answered By Laura Johnson VMD

    Veterinarian

    Published on September 5th, 2018

    Hi, thanks for using PetCoach! Thanks for the pictures. Actually the black spot on him are not fleas. Female fleas lay their eggs on the carpet and the larvae when they hatch stay on the carpet eating debris. Once they become adults they jump on the pet. What you are seeing are comedones, which are like black heads in people. Causes can be from cushings's disease or low thyroid (hormonal causes) or a skin infection. I would bathe him in a follicular flushing medicated shampoo. If the area doesn't improve then I would take her in to your Vet. https://www.drsfostersmith.com/product/prod_display.cfm?pcatid=21564 I wish you all the best!

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