Gangrene happens when body tissue dies because its blood supply has been lost or because of a serious infection. It most often affects the toes, feet, fingers, and hands, but it can also affect muscles and internal organs. Gangrene needs urgent medical assessment.
Symptoms
Symptoms depend on the type and location of the gangrene. Possible signs include:
- skin that becomes pale, blue, purple, red, brown, or black
- severe pain followed by loss of feeling
- swelling, blisters, or a wound that does not heal
- cold, firm, or numb skin
- foul smelling fluid from a wound
- fever or feeling generally unwell when infection is present
When to Get Emergency Help
Contact emergency services immediately if there is sudden severe pain, rapidly changing skin colour, loss of feeling, confusion, difficulty breathing, or signs of a serious infection. Do not wait for the symptoms to improve.
Causes and Risk Factors
Gangrene can develop when blood cannot reach part of the body. This may happen because of peripheral artery disease, diabetes, a blood clot, a serious injury, frostbite, or pressure on tissue. Some bacterial infections can also destroy tissue quickly.
Smoking, diabetes, poor circulation, a weakened immune system, and recent surgery or injury can increase the risk. People with diabetes should check their feet regularly and seek medical care for wounds, colour changes, or swelling.
Diagnosis
A healthcare professional may examine the affected area and arrange blood tests, imaging, or tests on tissue or fluid. The aim is to find the cause, check the blood supply, and identify infection.
Treatment
Treatment starts as soon as possible. It may include surgery to remove dead tissue, antibiotics for infection, and surgery or other procedures to restore blood flow. Oxygen therapy may be considered in selected cases. Severe gangrene may require removal of an affected toe, finger, or limb to stop further damage.
Reducing Risk
- Do not smoke.
- Follow your treatment plan for diabetes and vascular disease.
- Check your feet and skin for wounds or colour changes.
- Keep wounds clean and seek care if they do not heal.
- Protect skin from extreme cold and serious injury.
Sources
Reviewed: 28 August 2026. This page provides general information and does not replace medical assessment, diagnosis, or treatment.