Raynaud's phenomenon: A condition resulting in discoloration of fingers and/or toes when a person is exposed to changes in temperature (cold or hot) or emotional events.
The skin discoloration occurs because an abnormal spasm of the blood vessels causes a diminished blood supply. Initially, the digits involved turn white because of diminished blood supply, then turn blue because of prolonged lack of oxygen and finally, the blood vessels reopen, causing a local "flushing" phenomenon, which turns the digits red. This three-phase color sequence (white to blue to red), most often upon exposure to cold temperature, is characteristic of Raynaud's phenomenon.
Raynaud's phenomenon occurs with a number of conditions including rheumatic diseases (scleroderma, rheumatoid arthritis, systemic lupus erythematosus), hormone imbalance (hypothyroidism and carcinoid), trauma (frostbite, vibrating tools), medications (propranolol/INDERAL, estrogens, nicotine, bleomycin) and, uncommonly, cancer.
The phenomenon is named for the French physician Maurice Raynaud (1834-1881). |
Copyright © 1996-2003 MedicineNet,
Inc. All rights reserved.
MedicineNet, Inc. does not endorse any of the services or products offered
on this page.

Information in the MedTerms Medical Dictionary is
provided for informational purposes only and is not a substitute for
professional medical advice. You should not use this information for
diagnosing or treating a medical or health condition. You should carefully
read all product packaging. If you have or suspect you have a medical
problem, promptly contact your professional healthcare provider. |