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Why does my male dog have black bumps on his penis and nipples?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | neutered | 35 lbs

male dog has bumps on penis and nipples. the skin around the bumps has turned black

1 Answer

Most Helpful Answer

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Answered By David Elbeze, DVM, MRCVS

Veterinarian

Published on March 18th, 2019

This is probably caused by an allergic reaction. first of all make sure you de-flea Bear 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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