What is Raynaud's phenomenon?

Raynaud's (say "ray-NOHZ") phenomenon is a condition in which blood flow to the surface tissue of the hands and feet is temporarily decreased, usually as an overresponse to cold temperatures. There are two kinds of Raynaud's phenomenon. Primary Raynaud's, also known as Raynaud's disease, occurs by itself and is the most common form. Secondary Raynaud's, also called Raynaud's syndrome, usually occurs as part of another disease and usually begins after age 35.

Raynaud's phenomenon is common but often goes unreported. For most people with the condition, Raynaud's is more of a nuisance than a disability.

What causes Raynaud's phenomenon?

Primary Raynaud's has no known cause. Secondary Raynaud's may develop as a result of another disease such as lupus, scleroderma, rheumatoid arthritis, or atherosclerosis. Other causes of secondary Raynaud's include taking certain medicines, using vibrating power tools for several years, smoking, or having frostbite.

Exposure to cold is the most common trigger of an attack of Raynaud's phenomenon. In cold conditions, the body normally conserves heat by narrowing (constricting) blood vessels to the skin and opening (dilating) blood vessels to warm the internal parts of the body. During an attack of Raynaud's phenomenon, the body overreacts and severely restricts the flow of blood through small vessels to the skin. Emotional stress or certain medicines can also trigger an attack. An attack of Raynaud's phenomenon usually lasts only a few minutes, but in some cases it may last over an hour, especially if the surrounding temperature remains low.

What are the symptoms?

During an attack of Raynaud's, the small blood vessels (capillaries) that supply blood to the skin become narrow (constrict), limiting blood flow to the hands and feet or, less commonly, the nose or ears. This often causes fingers or toes to feel cold and numb and then turn white or blue. As blood flow returns and the fingers warm, they may turn red, or blue then red, and begin to throb and become painful.

How is Raynaud's phenomenon diagnosed?

Raynaud's phenomenon is diagnosed through a medical history and physical examination. There are no simple tests that can be used to diagnose the condition, so your doctor will rely on your description of your symptoms. Blood tests or other tests may be used to rule out other conditions that may be causing your symptoms.

How is it treated?

You may be able to prevent or relieve symptoms and limit attacks by avoiding the triggers of Raynaud's. Keep your body warm at all times. If you feel cold, your body will naturally redirect blood from your hands and feet to the central part of your body. If you can't keep the surrounding temperature above 68F to 70F, wear extra layers of clothing to remain warm. Also, reduce anxiety, quit smoking, and avoid medicines or other substances that trigger attacks, such as caffeine, cold medicines that contain pseudoephedrine, and beta-blocker medicines. Do not stop taking medicines your doctor has prescribed, such as beta-blockers, without talking with your doctor. If necessary, medicine, such as a calcium channel blocker, may be prescribed to increase blood flow to the hands and feet and to relieve symptoms.