Stomatitis (Feline) — Cat Health Glossary

Stomatitis

Feline chronic gingivostomatitis (FCGS) — severe, painful inflammation of the gums, inner cheeks, and throat in cats, driven by an abnormal immune response to oral bacteria. One of the most debilitating and painful chronic conditions in domestic cats.

Vet referral essential. Stomatitis cannot be managed at home. If your cat shows signs of mouth pain, book a vet appointment promptly — this is not a wait-and-see condition.

How to recognise it

Stomatitis produces some of the clearest behavioural signs of oral pain in cats. Look for:

Difficulty eating

Dropping food, chewing on one side, or refusing hard food entirely. May switch to liquid food or stop eating.

Excessive drooling

Often blood-tinged. The cat may hold its mouth open or make repeated swallowing movements.

Pawing at the mouth

Cats in oral pain frequently paw at or rub their face. Combined with hypersalivation, this is a clear prompt for a vet visit.

Severe halitosis

A strong, distinctive odour from the mouth — different from typical bad breath — due to tissue inflammation and secondary infection.

Weight loss

Caused by pain-driven food avoidance. Significant weight loss over weeks indicates the cat is suffering chronic pain.

Behavioural changes

Increased hiding, reluctance to be touched around the head, reduced grooming, depression.

What happens in the mouth

In a cat with stomatitis, the immune system mounts an extreme inflammatory response to dental plaque — the bacterial biofilm that builds on all teeth. The inflammation extends far beyond the gum line, affecting the mucous membranes of the cheeks, soft palate, and the tissue at the back of the throat (caudal stomatitis). The tissue becomes ulcerated, bleeds easily, and is intensely painful.

Why some cats develop this response while others do not is not fully understood. Genetic predisposition, viral co-infections, and immune dysregulation are all implicated. Research is summarised in a comprehensive Frontiers in Veterinary Science review (2020).

Treatment

Stomatitis does not respond reliably to antibiotics or to removing only some teeth. The most effective treatment in severe cases is full-mouth extraction — removing all teeth to eliminate the bacterial surface that drives the immune response. This sounds drastic, but cats adapt well to life without teeth and can eat wet and softened food comfortably. The WSAVA Global Dental Guidelines support this approach for refractory cases.

Approximately 60–80% of cats see significant improvement or full remission after extraction. The remainder may require immunosuppressive therapy or ongoing management with your vet.

Early dental care prevents more than stomatitis. Routine tooth brushing and regular veterinary dental checks reduce plaque — the trigger for this condition. Starting dental care while your cat is a kitten is significantly easier than introducing it to an adult cat. See the WSAVA recommendations for the basics.

Frequently asked questions

Is stomatitis the same as gingivitis in cats?

No, though they are related. Gingivitis is inflammation limited to the gums. Stomatitis (formally: feline chronic gingivostomatitis, FCGS) is much more severe and widespread — it extends beyond the gums to the back of the mouth, the cheek lining, and often the throat, causing intense pain. The WSAVA Global Dental Guidelines describe it as one of the most painful oral conditions in small animals.

What causes stomatitis in cats?

The exact cause is not fully understood, but it appears to be an abnormal immune response to oral bacteria (particularly plaque). Certain viral infections — feline calicivirus, feline herpesvirus, and FIV — are associated with higher prevalence. It is not a simple infection that responds to antibiotics alone. The Frontiers in Veterinary Science review (2020) summarises current understanding.

How is stomatitis treated?

The most effective long-term treatment for severe cases is full-mouth tooth extraction (all teeth removed). This eliminates the bacterial plaque that drives the immune response. Around 60–80% of cats improve significantly or go into remission after extraction. The remainder may need ongoing medical management. This is well-documented in the veterinary literature, including Jennings et al. (2015).

My cat has bad breath — could it be stomatitis?

Bad breath alone is more likely to be simple dental disease (tartar, gingivitis), which is very common in cats. Stomatitis is much more severe — affected cats typically drool heavily, have difficulty eating, paw at their mouths, and show obvious pain. If your cat has bad breath, book a dental check with your vet. Do not wait for obvious pain to appear.

Can stomatitis be prevented?

There is no guaranteed prevention, but regular dental care reduces the bacterial load that may trigger or worsen the condition. Daily tooth brushing from kittenhood is the gold standard, as recommended by the WSAVA Dental Guidelines. Keeping cats up to date on calicivirus vaccination also reduces one known risk factor.