Raynaud’s phenomenon, sometimes called Raynaud's syndrome or disease, is a condition in which cold temperatures or strong emotions cause blood vessel spasms that block blood flow to the fingers, toes, ears, and nose. Exposure to cold abnormally reduces blood circulation causing the skin to become pale, waxy-white or purple. Skin discoloration occurs because an abnormal spasm of the blood vessels causes a diminished blood supply to the local tissues.
Initially, the digit(s) involved turn white because of the diminished blood supply. The digit(s) then turn blue because of prolonged lack of oxygen. Finally, the blood vessels reopen, causing a local "flushing" phenomenon, which turns the digit(s) red. This three-phase color sequence (white to blue to red), most often upon exposure to cold temperature, is characteristic of RP.
Raynaud's phenomenon most frequently affects women, especially in the second, third, or fourth decades of life. People can have Raynaud's phenomenon alone or as a part of other rheumatic diseases. Raynaud's phenomenon in children is essentially identical to Raynaud's phenomenon in adults. Raynaud's phenomenon is particularly common in patients with scleroderma (seventy percent of patients with scleroderma develop Raynaud's phenomenon), although it may occur with other diseases or by itself
The most common trigger of RP is exposure to cold. In the cold, it's normal for the body to narrow the small blood vessels to the skin and to open the blood vessels to the inside parts of the body to keep the body warm. But with Raynaud's, the body overreacts and restricts blood flow through the small vessels to the skin more than necessary. An attack most often lasts only a few minutes. But in some cases it may last more than an hour.
There is no cure for primary Raynaud's, but it can be controlled by avoiding the things that trigger it. These triggers include cold temperatures, stress, smoking, caffeine, certain cold medicines and beta-blockers.