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My dog has a big red bump on his butt. What are the possible causes?

Updated On September 23rd, 2025

Pet's info: Dog | French Bulldog | Male | unneutered | 12 years and 5 months old | 27 lbs

Hi, my dog is 2 days that has this bump on his butt. It is big and red..I noticed it 2 days ago..what can it be ?

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4 Answers

Most Helpful Answer

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Answered By Andrea M. Brodie, DVM

Veterinarian

Published on December 30th, 2018

This could be a severely abscessed anal gland/sac or a tumor or a perineal hernia. This can only be diagnosed with a hands-on exam. You should have it examined by your veterinarian, as it is not possible to distinguish these by just looking at a photo. An abscess can usually be treated with antibiotics and/or be lanced, and a hernia may have to be fixed surgically. To identify a tumor, your vet may want to do a fine needle aspirate (he takes some material from the bump with a needle and then looks at it under the microscope) to determine whether the mass is concerning.

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9Pet Parents found this answer helpful

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    Answered By Angel Alvarado, LVT

    Licensed Veterinary Technician

    Published on March 29th, 2019

    It could be a ruptured anal gland abscess. An exam with your veterinarian will confirm this. Place an e-collar (cone) on her to prevent licking. If it is an abscess, it will need to be flushed and cleaned. Antibiotics and pain medications will likely be indicated.

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    Answered By Andrea M. Brodie, DVM

    Veterinarian

    Published on November 11th, 2018

    Ouch, that looks painful. This could be an abscessed anal sac, a cyst or a tumor. I suggest you take Norman to a veterinarian ASAP for an exam. An abscess can usually be treated with antibiotics and/or be lanced, and a cyst can be evacuated. Your vet may want to do a fine needle aspirate (he takes some material from the bump with a needle and then looks at it under the microscope) to determine whether the mass is concerning.

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    1Pet Parents found this answer helpful

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    Answered By Amy Poole, DVM

    Veterinarian

    Published on June 20th, 2017

    Unfortunately I can't see the lump on your dogs rear clearly in the picture. She may have a lipoma, which are common benign fatty tumors we see in older dogs, or something more worrisome. If it is on the anus, dogs can develop anal gland infections and abscess, as well as anal gland tumors. Any lump or bump that is changing and growing should be checked out by a veterinarian. A vet can do a fine needle aspirate of the lump to try to get some cells from it. Those cells can then be examined them under the microscope and hopefully give the vet and you a better idea as to what the lump is and if it needs to be moved or not.

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