| What it is | Freezing of skin & tissue |
| Common areas | Fingers, toes, ears, nose, cheeks |
| Warning stage | Frostnip (numb, pale, reversible) |
| Never | Rewarm if it may refreeze; don't rub |
Frostbite is the freezing of skin and underlying tissue from exposure to extreme cold, most often affecting fingers, toes, ears, nose, and cheeks. It progresses from frostnip (reversible numbness and pallor) to deep frostbite with hard, white or waxy, numb tissue. Refreezing thawed tissue causes severe damage, so rewarming should only be done when refreezing can be prevented.
This is general educational information, not medical advice. In an emergency, seek professional medical help.
Related cold risks
Frostbite often accompanies hypothermia, which is treated first; good layering helps prevent both.
Frequently asked questions
What are the signs of frostbite?
Early frostbite (frostnip) brings numbness, tingling, and pale or red skin that is still soft. As freezing deepens, skin turns white, gray, or waxy, feels hard or wooden, and loses sensation. After thawing, the area may blister and swell. Numb, hard, discolored skin in extreme cold signals serious frostbite.
What should you NOT do with frostbite?
Don't rub or massage the area (ice crystals tear tissue), don't use direct or excessive heat like a fire, and crucially, don't thaw frostbitten tissue if there's any chance it will refreeze — a refreeze causes far worse damage. Also avoid walking on frostbitten feet unless necessary for evacuation.
How do you treat frostbite in the field?
Get the person warm and out of the cold, treat any hypothermia first, remove constricting items, and protect the area. Definitive treatment is rapid rewarming in warm (not hot) water around 98–104°F, but only when refreezing can be ruled out — otherwise keep the part frozen and evacuate to medical care. Frostbite often accompanies hypothermia, which takes priority.
Sources
- Frostbite prevention — CDC
- Frostbite guidelines — Wilderness Medical Society