Cat Sores: Causes, Monitoring & When to See a Vet
Sores on cats may result from bites, allergies, infections, or self-trauma, and open or non-healing sores need veterinary attention.
Quick Answer
Sores on a cat may be caused by bite wounds, allergies, skin infections, parasites, or self-trauma from scratching and over-grooming. Sores that are open, draining, painful, or not healing should be evaluated by a veterinarian. Bite wounds can develop into abscesses, particularly in outdoor cats.
SYMPTOM TRIAGE
Answer a few questions about your cat's signs and receive general guidance on how urgently to seek veterinary care.
This tool does not diagnose conditions or replace a veterinarian.
What Sores Can Look Like
Sores on cats appear as areas of broken, damaged, or ulcerated skin. They may be open wounds, crusted lesions, or raised, swollen areas. Sores may ooze fluid or pus, may be surrounded by redness or hair loss, and may be warm to the touch.
What May Be Associated with Sores
Similar signs can have different causes, and the following are possible explanations a veterinarian may consider.
Bite Wounds and Abscesses
Cats that go outdoors or live with other cats may develop bite wounds that can become infected and form abscesses.
Flea Allergy and Self-Trauma
Itching from flea allergy, other allergies, or parasites can cause cats to scratch and chew until sores develop.
Skin Infections
Bacterial and fungal infections can cause sores, crusting, and hair loss.
Eosinophilic Granuloma Complex
This group of inflammatory skin conditions can cause raised sores, plaques, or granulomas, often on the lips, chin, abdomen, or thighs.
Burns or Chemical Injury
Contact with hot surfaces or harsh chemicals can cause skin sores.
What to Monitor
Tracking details helps a veterinarian assess the situation.
- Location, size, and appearance of sores
- Whether sores are open, crusted, or draining
- Whether the area is warm, swollen, or painful
- Whether the cat is scratching or licking the sores
- Whether sores are spreading or new ones are appearing
- Other signs: Lethargy, fever, reduced appetite, or hiding
What You Can Safely Do Next
Prevent the cat from licking or scratching at sores. Keep the area clean. Do not apply human wound treatments without veterinary guidance. If sores are open, draining, painful, or not healing, contact a veterinarian promptly.
When to Contact a Veterinarian
Some situations require immediate veterinary attention, while others may allow for monitoring. When in doubt, contacting a veterinarian is the safest approach.
Emergency Signs
Contact a veterinarian or emergency clinic immediately if you observe any of the following:
- Sores with signs of infection (swelling, pus, heat, or pain)
- Sores with lethargy, fever, or refusal to eat
- Abscesses that are swollen and painful
- Rapidly spreading skin lesions
- Sores with a foul odor or extensive tissue damage
These signs may indicate a serious condition that requires prompt evaluation. In the US, the ASPCA Animal Poison Control Center can be reached at 888-426-4435 if toxin exposure is suspected. In the UK, contact your veterinarian or the Veterinary Poisons Information Service for guidance.
Non-Urgent Signs
The following may warrant a routine veterinary call rather than emergency care:
- Small, superficial sores that are healing
- Mild scabbing with no signs of infection
Frequently Asked Questions
Why does my cat have sores on its skin?
Common causes include bite wounds, flea allergy, skin infections, parasites, and self-trauma. The location and appearance can help a veterinarian determine the cause. Any open, draining, or non-healing sore should be evaluated.
Can cat bite wounds heal on their own?
Small bite wounds may heal, but they often become infected and form abscesses. Abscesses typically need veterinary treatment including drainage. If the area is swollen or painful, contact a veterinarian.
SYMPTOM TRIAGE
If you are concerned about your cat's sores, use the symptom triage tool to get general guidance on how urgently you should seek veterinary care based on the signs you are observing.
This tool provides general information and does not replace a veterinarian's diagnosis.
Sources
- Cornell Feline Health Center. "Skin Disorders in Cats." Retrieved July 2026.
- Merck Veterinary Manual. "Dermatologic Diseases of Cats." Retrieved July 2026.
- VCA Hospitals. "Flea Allergy Dermatitis in Cats." Retrieved July 2026.
- ASPCA. "Common Toxic Hazards for Pets." Retrieved July 2026.
Disclaimer
This article and the PawAI Symptom Triage tool provide general information and do not replace examination, diagnosis, or treatment by a licensed veterinarian. If your cat shows emergency signs, contact a veterinarian or emergency clinic immediately.