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Raynaud’s phenomenon: what happens in an attack, the two types, getting a diagnosis, treatment, and living with it
For anyone whose fingers or toes turn white, then blue, in the cold, anyone just told they have Raynaud’s phenomenon, and the people beside them. The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS, part of the NIH) says Raynaud’s phenomenon causes the blood vessels in the extremities to narrow, restricting blood flow, usually in the fingers and toes, and usually from cold or emotional stress. In most people, lifestyle changes such as staying warm keep the symptoms under control; in severe cases, repeated attacks can lead to skin sores or gangrene. This page passes on, by name, what NIAMS says: what happens in an attack, the primary and secondary types, who gets it and what sets it off (including some medicines), how it is diagnosed and who treats it, the treatment, and what you can do day to day, from keeping your core warm to ending an attack. It builds the words to say to a provider, and prints a card for the visit.
Right now
- A whole hand, arm, foot or leg that suddenly turns cold, pale and painful: call 911 (ours).
- A finger or toe that turns black, or stays white or blue, cold and numb even after you warm it up: get care the same day, at an emergency room if you cannot reach a provider (ours). NIAMS says in rare cases a long attack can lead to gangrene, the death of tissue.
- An attack happening now: NIAMS says to put your hands or feet somewhere warm, such as under warm (not hot) water or a heating pad, or to whirl your arms or tuck your hands under your armpits. A new sore on a fingertip or toe: see a provider soon (ours).
More help
- Related: Lupus · A rash, an itch, or something on the skin: find the right page · When it’s dangerously cold.
- Habits and feelings: When you want to quit smoking · Anxiety.
- Day to day: Symptom diary · My medicines list.
- Care and costs: When you need a doctor and can’t pay · When medicine costs too much · Get ready for your appointment.
- In a crisis: Help right now (988, 911). All our free tools.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor or nurse has reviewed it. The facts were read on October 15, 2026 on NIAMS’s Raynaud’s Phenomenon page, both parts: Overview, Symptoms, & Causes and Diagnosis, Treatment, & Steps to Take (NIH, last reviewed July 2024), and on its Spanish twin, Fenómeno de Raynaud (August 2021), which carries the same facts. Ours: calling 911 for a whole hand, arm, foot or leg that suddenly turns cold, pale and painful; getting care the same day, at an emergency room if you cannot reach a provider, for a finger or toe that turns black, or stays white or blue, cold and numb after warming; seeing a provider soon for a new sore on a fingertip or toe; testing warm water with a part of you that is not numb; writing down your attacks and taking photos; telling a provider about your work; not stopping or changing a medicine on your own; asking a pharmacist before a cold medicine; asking what a test or treatment would change and what it costs; and the order of the steps. What we left out: any medicine to treat it, any brand or dose, any supplement, remedy or product, and NIAMS’s research pages. This page saves nothing and loads no trackers.