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My dog has a bump and her hair is turning dark. What's wrong?

Updated on September 23rd, 2025

Pet's info: Dog | Chihuahua | Female | spayed | 9 years and 6 months old

My dog has a very small bump on her back, and a small patch of hair on her right side seems darker, almost turning black. I'm not sure if this is anything serious or maybe if she got into something?

1 Answer

Most Helpful Answer

Answered By Menolly Cote, DVM, CVA

Veterinarian, Certified Veterinary Acupuncturist

Published on July 15th, 2017

Increased pigmentation in the skin can be a result of hormonal changes such as those seen with hypothyroidism or chronic inflammation such as with skin allergies or yeast infections. The bump in the picture could be due to inflammation as well or could be a cyst, wart or skin tumor. If the bump is getting larger, does not go away or seems to be bothering Rhonda, I would recommend that you have her seen by your veterinarian. The changes in skin color may resolve with time but if they do not or seem to be getting worst, I would recommend seeing a veterinarian. They may recommend checking thyroid levels to rule out hypothyroidism.

1Pet Parents found this answer helpful

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