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Frostbite

Dr Lynn Thomas, OStJ, BSc, MB.BS, MA, FRCPClinically reviewed: 28/04/2025

Frostbite can happen when exposed to freezing cold temperatures. Find out what to look for and how to perform first aid.

What is frostbite?

Frostbite happens when part of the skin and other tissues freeze due to low temperatures. It can lead to loss of sensation and eventually tissue death and gangrene. This usually happens with prolonged exposure to freezing cold temperatures, particularly if there is added wind chill.

Signs and symptoms

Frostbite can affect anywhere on the body, but most commonly affects the extremities, such as fingers and toes, or the tip of the nose, ears, or lips.

Look for:

  • sensation of 'pins and needles'

  • paleness of the area and numbness

  • hardened and stiffened skin

  • colour change to the skin. The skin may change from white to mottled and blue. On recovery, the skin may be red, hot, painful and blistered. When gangrene occurs, the skin may become black due to the loss of blood supply.

What to do

  1. 1

    Help move the casualty indoors or to somewhere warm.

  2. 2

    Once inside, gently remove any constricting items such as rings, gloves, and boots.

  3. 3

    Next, warm the affected part with your hands, in your lap.

    • Do not rub the area as this could damage their skin.

    • Do not expose the affected part of the body to direct heat.

  4. 4

    Place the affected part into warm but not hot water – around 40°C. Dry the area carefully and put on a light dressing, ideally a gauze bandage from your first aid kit.

  5. 5

    Once you’ve done that, help them to raise the affected part to reduce swelling. If the casualty is an adult, you can suggest they take the recommended dose of paracetamol. If the casualty is a child, you can give them the recommended dose of paracetamol syrup.

    • Do not give aspirin to anyone under the age of 16 or anyone who is known to be allergic.

  6. 6

    Take or send them to hospital.

    Someone suffering from frostbite is likely to be experiencing hypothermia, so be sure to look for the signs of this and treat if necessary.

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