Raynaud’s phenomenon is a condition that affects the blood vessels in the extremities—generally, the fingers and toes. It is characterized by episodic attacks, called vasospastic attacks, in which the blood vessels in the digits (fingers and toes) constrict (narrow), usually in response to cold temperatures and/or emotional stress. When this condition occurs on its own, it is called primary Raynaud’s phenomenon. When it occurs with another condition such as scleroderma or lupus, it is called secondary Raynaud’s phenomenon. It affects 3-4% of U.S. adult population, predominately women by 3 to 1 ratio with positive family history in 20-30% of patients. The phenomenon usually occurs in the second or third decade of life.
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