Chilblains (pernio): when skin reacts to cold

What it is

Cold narrows small blood vessels. During rewarming, surface vessels can widen faster than deeper circulation adapts, contributing to leakage and inflammation. Chilblains often appear several hours after exposure rather than while you are still outside.

They are not frostbite: tissue is not frozen. Recurrent or severe pernio can occasionally be associated with circulation problems, autoimmune disease, medications or low body weight, so repeated episodes deserve discussion with a clinician.

What it looks and feels like

• Small red, purple, blue-brown or darker swollen patches after cold or damp exposure.
• Itching, burning, tenderness or pins-and-needles sensation.
• Typical sites are fingers, toes, ears, nose and lower legs.
• Blisters or superficial sores can occur in more severe cases.
• Symptoms may become more noticeable as the area warms.

Causes, triggers and risk factors

• Cold, damp weather and rapid temperature changes.
• Tight footwear or clothing that reduces circulation.
• Smoking or nicotine exposure, which constricts blood vessels.
• Low body weight, poor circulation or long periods of inactivity.
• Underlying connective-tissue disease in a minority of recurrent cases.

Treatment and self-care

Move indoors, remove wet clothing and warm the area slowly with dry layers and a comfortable room temperature. Do not place affected hands or feet against a radiator, hot-water bottle or very hot water. Avoid scratching; protect blisters or broken skin with a clean loose dressing.

A pharmacist can advise on itch relief and suitable skin protection. Keep the whole body warm, not just the affected part. Do not massage painful or damaged skin aggressively.

Conditions that can look similar

• Frostbite: numb, pale or hard skin after severe cold; needs urgent assessment.
• Raynaud phenomenon: episodic white-blue-red finger color change, usually without persistent swollen patches.
• Contact dermatitis: relates to an exposure rather than cold and often has clearer contact distribution.
• Cellulitis: progressive warmth, pain and spreading redness, often with illness.
• COVID toes or vasculitis: can resemble pernio and require context and assessment.

Preventing chilblains

Warm up before going outside, wear moisture-wicking socks, roomy insulated footwear and waterproof gloves, and change wet items promptly. Keep your home at a stable temperature when possible. Rewarm gradually after exposure and avoid smoking.

If episodes are frequent despite prevention, a clinician may investigate circulation or autoimmune symptoms and, in selected cases, consider prescription treatment that affects blood vessels.

When to see a healthcare professional

• Lesions have not improved after 2–3 weeks.
• There is pus, spreading redness, fever or worsening pain.
• You repeatedly develop chilblains or they occur without cold exposure.
• You have diabetes, poor circulation or a weakened immune system.
• Skin is numb, hard, pale or blackened after severe cold exposure.

Sources and further reading

We use established public-health and dermatology references and link them directly so you can verify the guidance and read further.

• Chilblains — NHS
• Chilblains patient information — Oxford Health NHS Foundation Trust

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