What causes the circulation in the finger tips to stop and fingers to become numb?

Loss of Circulation in Fingertips

Raynaud's phenomenon (RP), also known as Red, White and Blue disease- is a condition resulting in a series of discolorations of the fingers and/or the toes after exposure to changes in temperature (cold or hot) or even emotional events ie.. anxious at the dentist or at a job interview. It is due an abnormal spasm of the blood vessels which results in 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.

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