Causes

Doctors don't completely understand the cause of Raynaud's attacks, but blood vessels in the hands and feet appear to overreact to cold temperatures or stress.

Blood vessels in spasm

With Raynaud's, arteries to your fingers and toes become narrow and briefly limit blood supply when exposed to cold or stress. Over time, these small arteries can thicken slightly, further limiting blood flow.

Cold temperatures are most likely to trigger an attack. Exposure to cold, such as putting your hands in cold water, taking something from a freezer or being in cold air, is the most likely trigger. For some people, emotional stress can trigger an episode.

Primary vs. secondary Raynaud's

There are two main types of the condition.

• Primary Raynaud's. Also called Raynaud's disease, this most common form isn't the result of an associated medical condition. It can be so mild that many people with primary Raynaud's don't seek treatment. And it can resolve on its own.

• Secondary Raynaud's. Also called Raynaud's phenomenon, this form is caused by an underlying problem. Although secondary Raynaud's is less common than the primary form, it tends to be more serious.

  Signs and symptoms of secondary Raynaud's usually appear around age 40, later than they do for primary Raynaud's.

Causes of secondary Raynaud's include:

• Connective tissue diseases. Most people who have a rare disease that leads to hardening and scarring of the skin (scleroderma) have Raynaud's. Other diseases that increase the risk of Raynaud's include lupus, rheumatoid arthritis and Sjogren's syndrome.
• Diseases of the arteries. These include a buildup of plaques in blood vessels that feed the heart, a disorder in which the blood vessels of the hands and feet become inflamed, and a type of high blood pressure that affects the arteries of the lungs.
• Carpal tunnel syndrome. This condition involves pressure on a major nerve to your hand, producing numbness and pain in the hand that can make the hand more susceptible to cold temperatures.
• Repetitive action or vibration. Typing, playing piano or doing similar movements for long periods and operating vibrating tools, such as jackhammers, can lead to overuse injuries.
• Smoking. Smoking constricts blood vessels.
• Injuries to the hands or feet. Examples include a wrist fracture, surgery or frostbite.
• Certain medications. These include beta blockers for high blood pressure, migraine medications that contain ergotamine and sumatriptan, attention-deficit/hyperactivity disorder medications, certain chemotherapy agents, and drugs that cause blood vessels to narrow, such as some over-the-counter cold medications.