Medication to Treat Rodent Ulcers for Cats

These lips have never touched a rodent, but somehow I got a rodent ulcer?

These lips have never touched a rodent, but somehow I got a rodent ulcer?

Rodent ulcers have nothing to do with rats and mice. They're sores you might find on Kitty's lips or inside his mouth. In order to get rid of rodent ulcers, you and your vet must determine what's causing them, since they're often the result of an allergic reaction.

Eosinophilic Granuloma Complex

The scientific name for rodent ulcer is eosinophilic granuloma complex. Years ago, people believed cats got these sores from eating rodents, but that's an old wives' tale. Eosinophils, a type of white blood cell, are designed to protect Kitty's body from parasites; but sometimes they misidentify allergens as parasites, with lesions as the result. While some rodent ulcers are barely noticeable, others appear pink and yellowish, oozing and inflamed. In some cases, infection results. Because eating becomes painful, Kitty might lose weight.


Some cats develop rodent ulcers as a reaction to an allergen. If that's the case, Kitty may not need medication. If they're caused by a food allergy, a change of diet can do the trick. If fleas are the culprit, a topical monthly flea preventative solves the problem. Your vet conducts allergy tests on blood and skin samples from Kitty. In certain cases, environmental allergens such as mold and pollens cause the rodent ulcers. Besides medications such as antihistamines, air purifiers in rooms in which Kitty dwells might help, by filtering out such allergens.


If there's no obvious allergen causing the rodent ulcer, or if it's very large and hurting Kitty, your vet might prescribe steroids to reduce inflammation and get rid of it. However, Kitty might have to take these steroids for a long period of time in order to eliminate the lesion or prevent it from recurring. Steroids also have side effects, sometimes serious, so discuss the particular medication with your vet.

Other Medications

Depending on the size and condition of the rodent ulcer, the vet might prescribe antibiotics or anti-inflammatories to prevent infection and reduce pain. In severe cases, immuno-suppressive drugs might be necessary.


Prescription medication is not the only thing that helps keep rodent ulcers at bay. Some over-the-counter supplements containing essential fatty acids may aid in getting rid of the sores. These include fish oil and flaxseed supplements. Since giving Kitty a gelcap isn't easy, open it and mix it into his food. Even though you can purchase these supplements on your own, always tell your vet about any over-the-counter items you give Kitty.

About the Author

Jane Meggitt has been a writer for more than 20 years. In addition to reporting for a major newspaper chain, she has been published in "Horse News," "Suburban Classic," "Hoof Beats," "Equine Journal" and other publications. She has a Bachelor of Arts in English from New York University and an Associate of Arts from the American Academy of Dramatics Arts, New York City.

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