How to Recognise the Stages of Frostbite, and When to Get Help

When the temperatures are low and you’re outdoors, it doesn’t take long for your fingers to start feeling cold and stiff. Depending on the weather and how long they’re exposed, they may start to feel numb, or turn red. But is this a normal reaction to the cold, or the beginning of frostbite?

That’s a great question — and one that isn’t necessarily answered (at least very clearly) by many of the safety guidelines on frostbite. That’s because they often only mention skin colour and appearance, like turning pale (yellow or white) and becoming waxy and shiny.

But what if your skin is always kind of pale and waxy-looking? Or you aren’t sure what counts as “pale” in relation to your usual skin colour? That’s when you look for the other signs of frostbite, which are broken down by stages. Here’s what to know.

What is frostbite?

Frostbite is more than simply feeling cold: It’s an injury that could permanently damage body tissues — especially in the nose, ears, cheeks, chin, fingers, or toes.

According to the Cleveland Clinic, temperatures in the minus digits are low enough to cause frostbite, and the colder it is outside, the faster frostbite can set in. For example, when the wind chill is -25°C or lower, it could take less than a half an hour.

The stages of frostbite

There are three stages of frostbite: Frostnip, superficial frostbite, and deep frostbite, and each has their own signs and symptoms.

Frostnip

The tricky part about frostnip is that you may not notice any signs at all — or just assume that it’s to be expected in cold weather. The symptoms of frostnip can include skin turning red or a pale white, and/or feeling cold, numb, or tingly. These are warning signs from your body to get somewhere warm.

After rewarming frostnipped skin, small red bumps called “chilblains” may form, but typically go away on their own. Frostnip doesn’t cause permanent damage.

Superficial frostbite

Superficial frostbite includes all the symptoms above, except instead of feeling cold, your skin may begin to feel warm. That may appear to be a good sign, but it’s actually the water in your skin gradually freezing and transforming into ice crystals. Your skin may get hard, waxy, and/or shiny; you may also have difficulty moving because of stiff muscles and joints, and experience clumsiness and/or a loss of coordination.

After rewarming skin with superficial frostbite, parts may turn purple or blue and painful (like a bruise) as well as burn. Or, if areas of the skin are still red, they may start to peel and feel like a sunburn. This is a sign to get immediate medical attention. Lastly, fluid-filled blisters may appear 12 to 36 hours later.

Deep frostbite

At this point, total numbness usually sets in, and a person’s movement and coordination are significantly impacted. Skin may turn white or bluish-grey.

Large blisters will likely appear a day or two after the skin has been rewarmed. Finally, the frostbitten skin turns hard and black and either falls off itself, or needs to be surgically removed.

When to get help

Anything beyond frostnip — meaning superficial or deep frostbite — need professional medical attention, especially if any of these symptoms are present, according to the Mayo Clinic:

• Hard, cold, blotchy skin
• Increased pain, swelling, inflammation or discharge in the area that was frostbitten
• Fever
• Symptoms of hypothermia (intense shivering, slurred speech, drowsiness and loss of coordination)
• New, unexplained symptoms

But this isn’t a situation where you can wait around for medical help and hope for the best. Instead, follow these directions for treating frostbite until you’re able to see a professional.