Typical behaviour
The cat tilts its head, eats slowly and leaves part of the food. It may prefer soft food on one side. Sometimes it “drops” food from its mouth and picks it up again — to chew with the other side.
Possible dental causes
Tooth resorption (TR) on one side is the most common cause in cats. Periodontitis, a fractured canine, a deep periodontal pocket, localised FCGS.
- Tooth resorption (TR) — most often diagnosed in cats
- Periodontitis on one side
- A fracture or infection of a particular tooth
- FCGS — if the lining of the mouth is affected on the same side
Why a cat may keep eating even when one side hurts
The cat adapts how it eats — it chews on the healthy side. The owner sees a “normal appetite”. This is the classic history before a diagnosis of TR.
Less grooming of the coat and avoiding being touched on the face are additional signs.
How to find the cause
An examination of the awake cat often does not show the full picture. A full diagnostic work-up under anaesthesia with dental X-rays is the most reliable route. TR cannot be assessed reliably without radiographs.
What the owner should do
Do not ignore a “strange habit”. Book a consultation. Describe which side the cat eats on and how long this has been going on.
Related symptoms
If the cat grooms its coat less — see the article on grooming. If it keeps eating despite diseased teeth — there is a separate article on hidden pain.
When to see a vet
- The cat has been eating on one side for more than a week
- There is also drooling, a bad smell or avoidance of being touched on the face
- The cat is losing weight or eating less
- The cat avoids dry food
- The cat suddenly jerks its head back or stops eating mid-meal
- Grooming has decreased
- “Worn-away” or darkened teeth are visible
- TR has already been diagnosed — a follow-up check
What not to do at home
- Do not ignore a “strange habit” without an examination
- Do not force the cat to eat from the “painful” side
- Do not put it off because the appetite is normal
- Do not treat with antibiotics without a diagnosis
Frequently asked questions
Most often the cause is dental. I assess the mouth and, if needed, other factors.
Yes, cats mask pain. One-sided chewing is a frequent compromise.
Often, yes, in cats. Dental X-rays confirm the diagnosis.
It reduces discomfort for a while, but it does not treat the cause.
Yes, for a full assessment and dental X-rays.
Sources and professional guidelines
- WSAVA Global Dental GuidelinesGlobal guidelines for veterinary dentistry
- AAHA Dental Care Guidelines for Dogs and CatsClinical guidelines for dental care
- AVDC: Tooth ResorptionClassification of tooth resorption (TR) by stage and type
© dr.vetstomat. Original content.
Copying and publishing text and visual materials without the author's written consent is not permitted, except as allowed by law.