
If your cat has a warm, painful swelling or a wound that’s suddenly oozing smelly pus, they likely have an abscess. Cat abscesses are very common, especially in cats that go outdoors and get into fights. They usually need a vet’s care, but most cats recover quickly with treatment.
An abscess is a pocket of pus under the skin. Most cat abscesses start with a bite wound from another cat. Cats’ teeth are sharp and narrow, so bites make small punctures that close over quickly. Bacteria from the mouth get trapped under the skin and multiply, forming an abscess within a few days.
Abscesses often form where cats bite each other during fights:
Mouth abscesses can also form from dental disease.

Our articles on my cat is hiding and not eating and why your cat may be drooling explain other signs your cat may be unwell.
Abscesses often rupture on their own, leaving an open wound that drains pus and blood. If this happens:

Treatment may include:
Never give your cat human medicine or leftover antibiotics. Many human pain relievers are toxic to cats.
With treatment, most abscesses heal within one to two weeks:
Call your vet if the swelling comes back, the wound gets bigger, or your cat stops eating.
Bite wounds can spread feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). Your vet may recommend testing a few weeks after a fight.
Some drain and heal, but many need treatment to fully clear the infection.
Your vet may recommend warm compresses to help drainage. Ask first.
Talk to a licensed vet 24/7, even on holidays, by chat, voice call or video call. Your first month is free with code FREEMONTH, then US $9.99/month, at NYPTeleVet.com. One membership covers up to 6 pets, and you can cancel anytime.
Our vets can’t prescribe medication, but they’ll tell you what’s likely needed and when an in-person visit is the next step.
⚠️ Disclaimer: NYP TeleVet is not a substitute for professional veterinary care. For emergencies (trouble breathing, seizures, severe bleeding, collapse), go to the nearest veterinary clinic immediately.
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