Raynaud syndrome/ phenomenon.
The skin turns white and sometimes blue because of a reduced blood supply to the small blood vessels.
Quite often painful and a burning sensation as the blood returns, the skin then turns red.
Eponymously named after the physician, Auguste Gabriel Maurice Raynaud, who first described it in his doctoral thesis in 1862.
Episodes are typically triggered by cold, emotional stress, prolonged vibration, smoking, thyroid problems, and certain medications, such as birth control pills.
The primary treatment is avoiding the cold.
Other measures include the discontinuation of nicotine or stimulant use. Medications for treatment of cases that do not improve include calcium channel blockers and iloprost.
Little evidence supports alternative medicine.
Severe disease may rarely be complicated by skin sores or gangrene.