Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Gangrene is death of tissue from lost blood supply or severe infection. In cats, causes include blood clots (such as a saddle thrombus affecting the back legs), severe infections from bite wounds, frostbite, burns, and constricting items like rubber bands, hair ties, or bandages that are too tight. Affected tissue becomes cold, discolored, and painful, then dark and dry or wet and foul-smelling. It needs a vet urgently.
Signs
- Skin that’s pale, blue, gray, or black
- Cold paws, tail, or ear tips
- Swelling, foul smell, or discharge
- Severe pain, or later loss of feeling
- Fever and lethargy with infection
Causes
- Aortic thromboembolism (saddle thrombus)
- Infected bite wounds or rapidly spreading infections
- Frostbite of ears, tail, or paws
- Burns
- Rubber bands, hair ties, or string wrapped around a limb or tail
- Tight bandages or casts
What to do
- Go to a vet or emergency clinic right away
- If you find a band or string, only cut it off if you can do so safely without injuring the skin
- Keep the area clean and protected
Treatment
- Pain relief, fluids, and antibiotics
- Removal of dead tissue
- Amputation of a toe, tail, or limb in some cases
- Treating the underlying cause, such as heart disease
More: paralysis and blood clots in cats.
Sources
- Merck Veterinary Manual: Arterial thromboembolism in cats
- Merck Veterinary Manual: Frostbite in animals
- Merck Veterinary Manual: Wound management in small animals
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.