The difference between gingivitis and stomatitis is a subtle one.
Both cause inflammation, redness and soreness in the mouth, with gingivitis being limited to where the gums meet the teeth and stomatitis being inflammation of any of the pink mucus membranes (gum) lining the inside of the mouth.
This is a common condition, and there are a number of theories as to what causes gingivitis/stomatitis. No matter what the inciting cause, the result is the same — pain and discomfort when the cat eats.
There are several different ways of treating gingivitis/stomatitis, but frequently this is a matter of control rather than cure — trying to keep the cat comfortable and reducing the soreness as much as possible.
Cats with gingivitis/stomatitis usually have bad breath. They may even have smelly fur because their saliva smells bad, which is then spread over their coat when they groom.
The gums can be incredibly tender, and this shows at mealtimes with the cat seems hungry but is also anxious about eating. In severe cases, the cat may even growl at the food as she eats or be a very messy eater, letting food drop from her mouth as she chews.
In the worst cases, the cat may stop eating, and sometimes you may notice bloodstained fur on her forearms from where she rested her chin and drooled bloody saliva.
Even among feline specialists, there is a lot of debate about the causes of gingivitis/stomatitis.
But rather than some experts being right and some being wrong, it seems most likely that this condition has lots of causes. The confirmed reasons include viral infections such as calici virus, feline leukemia virus and feline immunodeficiency virus.
It is also thought that some cats mount an autoimmune reaction against their own teeth, and the gums become inflamed as they try to repel the teeth as something foreign that shouldn’t be there.
Some cats develop gingivitis/stomatitis because of illness elsewhere in the body, such as diabetes mellitus or kidney disease. These conditions cause the body’s immune system to dip below normal, and also some of the toxins produced as a result of disease irritate the gums.
This video shows Sampson the rescue cat with suspected stomatitis because of his inflamed and red gums:
A diagnosis of gingivitis/stomatitis is made by visual inspection of the mouth.
A few conditions mimic gingivitis/stomatitis, and sometimes a biopsy is taken to rule out more sinister options (such as cancer). Screening blood tests can help identify precipitating illnesses (such as kidney disease).
Dental X-rays are also useful in detecting damaged teeth or retained tooth roots (because these may act as a focus for autoimmune activity).
Keeping the teeth as clean as possible helps keep the amount of bacteria in check.
Severe cases may need the teeth extracted to remove a focus of immune stimulation.
Controlling secondary gum infections with antibiotics is a big part of treatment. There has been some success in using immune modifying drugs, such as interferon, for this problem. The interferon is injected into the gums (with the cat under general anesthetic) and also given daily by mouth.
Keeping the cat in good health helps strengthen the immune system and fight off viral infections, and vaccination against cat flu (herpes and calicivirus) and feline leukemia virus can reduce the risk. Apart from this, observing rigorous dental hygiene can reduce the severity and frequency of flare-ups.
- “Gingivitis stomatitis in cats.” Williams & Aller. Vet Clin North Am Small Anim Pract, 22: 1362–1383.
- “Chronic stomatitis in the cat.” Gaskell & Knowles. Veterinary Annual. 28th edition. 246–250.
This pet health content was written by a veterinarian, Dr. Pippa Elliott, BVMS, MRCVS. It was last reviewed Dec. 23, 2014.