Raynaud’s phenomenon is an exaggerated form of vasoconstriction – the body’s natural response to cold and stress. It results from a spasm of the small arteries that supply blood to the fingers. This spasm temporarily decreases blood flow, resulting in cold, painful, and discolored fingers.
How It Occurs
Vasoconstriction is a normal process that is triggered when the body encounters a cold environment. The sympathetic nervous system causes the blood vessels in the extremities to constrict, keeping blood and warmth in the body’s core. Raynaud’s phenomenon is a misfiring of this process, causing abnormal vasoconstriction.
Raynaud’s phenomenon can be caused by several medical conditions that affect the vascular system of the hands, including lupus and other connective tissue diseases, rheumatoid arthritis, arterial disease, and trauma. It can also be caused by smoking and by taking certain medications.
Raynaud’s disease, a condition often confused with Raynaud’s phenomenon, also results in vasoconstriction of the fingers. But while Raynaud’s phenomenon is caused by an underlying medical condition, Raynaud’s disease occurs without any underlying medical condition – its cause is not fully understood. Attacks of Raynaud’s disease are triggered by cold and stress, and are most common in young women.