Raynaud’s disease, also called Raynaud's syndrome or Raynaud's phenomenon, is when blood vessels in your fingers, toes, and other extremities temporarily overreact to low temperatures or stress. For most people, it isn’t a serious health problem.

Raynaud's (ray-NOSE) disease causes some areas of the body — such as fingers and toes — to feel numb and cold in response to cold temperatures or stress. In Raynaud's disease, smaller blood vessels that supply blood to the skin narrow.

Raynaud’s (pronounced ray-nodes) syndrome is a disorder that affects small blood vessels in your fingers and toes. It may also affect blood vessels in your nose, lips or ear lobes. Raynaud’s causes you to have episodic spasms, called vasospastic attacks, in response to cold temperatures or stress.

Raynaud’s phenomenon occurs when the blood vessels in your extremities—most commonly your fingers and toes—overreact to cold temperatures or stress. Under normal circumstances, the body reduces blood flow to these areas in response to cold, helping to preserve warmth for your vital organs.