Mouth Ulcers in Cats UK — Causes, Signs & When to See a Vet

According to the PDSA and International Cat Care, mouth ulcers are sore, red or yellow areas on the gums, tongue, palate or lips. Owners may not see ulcers directly — cats often hide mouth pain — but behaviour changes are telling:

• Drooling or wet chin fur — see Cat drooling excessively
• Bad breath (halitosis)
• Pawing at the mouth or shaking the head
• Dropping food or chewing on one side only
• Not eating or preferring soft food — see Cat not eating
• Weight loss over days to weeks
• Hiding or aggression when the face is touched

Any cat that has not eaten for 24 hours needs veterinary attention the same day.

Dental disease

Tartar, gingivitis and tooth root abscesses are the most common cause of oral pain in adult cats. Bacteria under the gumline inflame tissue and create painful lesions. Regular Cat dental care UK reduces risk.

Feline calicivirus (FCV)

FCV is a common upper respiratory virus in multi-cat households and rescue cats. Some strains cause painful tongue and gum ulcers alongside sneezing and eye discharge. Vaccination reduces severity but does not prevent all strains — see Cat vaccination schedule UK.

Feline chronic gingivostomatitis (FCGS)

FCGS is severe inflammation of the gums and back of the mouth. Affected cats may have widespread ulcers and extreme pain. Diagnosis and treatment often need a vet with dental expertise; extraction of affected teeth is sometimes required.

Kidney disease and other illness

Advanced Kidney disease in cats can cause uremic stomatitis — ulcers linked to toxin build-up. Other systemic diseases may also affect the mouth; blood tests help rule these in or out.

Burns and toxins

Chewing lilies, household cleaners, or hot food can burn the mouth. Never use human mouth gels or aspirin products on cats — they are toxic.

Your vet will examine the mouth (often under sedation for a full look), check for FCV, dental disease and systemic illness, and may recommend:

• Blood tests and blood pressure (especially in older cats)
• Dental X-rays and extractions if needed
• Pain relief safe for cats — never human ibuprofen or paracetamol
• Syringe feeding or appetite stimulants if eating is unsafe short term
• Referral for complex stomatitis or oral surgery

• Offer soft, warm food (tinned fish in water, chicken baby food with no onion/garlic)
• Keep fresh water nearby
• Avoid forcing the mouth open — you may worsen pain or get bitten
• Do not use human dental products unless your vet advises

• Annual dental checks from age one
• Vaccination against core cat viruses including calicivirus
• Avoid lilies and toxic houseplants — see Toxic houseplants pets UK
• Brush teeth if your cat tolerates it — your vet can demonstrate technique

• Cat dental care UK
• Cat not eating
• Cat drooling excessively
• Cat respiratory infection UK