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Ask Dr. Paola – HELP! How Can I Help My 15-year-old Cat With Rodent Ulcers? (September 7, 2026)

By Radim Chudej · Written by Dr. Paola CuevasVet Approved
Dr. Paola Cuevas
Reviewed & Fact-Checked byDr. Paola CuevasMVZ (Veterinarian)
Dr. Paola Cuevas is the Senior In-House Veterinarian at Pangolia, the parent company of Catster. She has over 18 years of experience as a veterinarian and animal behaviorist. Paola's focus is on preventive medicine and animal welfare. Paola has a large range of skills in from diagnostic imaging to nutrition and clinical pathology. Paola enjoys sharing her extensive knowledge of animal training with our Catster readers and is always happy to answer reader questions as our in-house veterinarian.View authorThe information is current and up-to-date in accordance with the latest veterinarian research. Read about our vets
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Ask Dr. Paola – HELP! How Can I Help My 15-year-old Cat With Rodent Ulcers? (September 7, 2026)

Welcome to our "Ask Dr. Paola" series, where every Monday we bring expert advice straight from Dr. Paola Cuevas (MVZ) to help our readers better understand their cat's health and well-being.

Whether you're a new pet parent or a seasoned cat lover, Dr. Paola is here to provide answers to your most pressing questions. From nutrition tips and preventive care to troubleshooting common behavioral issues, Dr. Paola is ready to offer insights that will keep your kitty happy, healthy, and feline fine. Stay tuned for expert guidance on a range of topics that matter most to you and your cat, so you can make informed decisions and provide the best possible care for your furry companion. ‎

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HELP! How Can I Help My 15-year-old Cat With Rodent Ulcers?

"Dear Dr Paola,

My 15-year-old cat, Sonny, has had rodent ulcers in his mouth for several years. He has gone through injections that seemed to work for a while, and I give him a supplement called Nutra Thrive daily. This helped for a couple of years, but now the problem has returned. He eats well, but now he just lies around, and it appears his mouth is painful.

Any help here would be appreciated."

- Mary Hellen

Dear Mary Hellen,

I am glad Sonny is still eating, but the change in his behavior is important. “Rodent ulcers,” more accurately called indolent or eosinophilic ulcers, are part of the feline eosinophilic granuloma complex and are commonly associated with hypersensitivity reactions. They are often not very painful themselves, so if Sonny is now lying around and appears uncomfortable, I would not assume that the ulcer alone explains everything.

Because Sonny is older and this problem has changed after years of treatment, I would recommend a veterinary examination soon, ideally including a careful oral examination under sedation or anesthesia if needed. The veterinarian should make sure this is truly an eosinophilic ulcer rather than another painful oral condition, such as dental disease, feline chronic gingivostomatitis, tooth resorption, an oral tumor, or secondary infection.

Persistent or unusual ulcers, particularly those that are focal or do not respond as expected, may warrant a biopsy because several different diseases can look quite similar from the outside. The previous injections may have been corticosteroids, which commonly make eosinophilic lesions improve, but repeated or long-term steroid treatment in a senior cat deserves particular care because the risks and benefits can change as a cat ages.

It is also worth investigating potential underlying triggers, especially strict flea control and, when appropriate, a properly conducted dietary elimination trial. Think of the ulcer as the smoke rather than the fire; treating the visible lesion can help, but identifying what is driving the inflammation is what may reduce recurrence. For now, I would prioritize getting Sonny's mouth and overall health assessed rather than relying on the supplement alone. His continued appetite is encouraging, but cats can be remarkably stoic about oral pain, and becoming unusually quiet or withdrawn can be an important indication that they are suffering. A senior-cat examination with oral evaluation, appropriate bloodwork, and a discussion of whether dental radiographs or biopsy are warranted would be a sensible next step.

Kind regards,

- Dr. Paola

This article is a part of our weekly Ask Dr. Paola series

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Radim Chudej
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