what is raynaud's phenomenon treatment
From Wikipedia, the free encyclopedia. In medicine, Raynaud's /reÉªËnoÊz/ Disease or Raynaud phenomenon is excessively reduced blood flow in response to cold or emotional stress, causing discolouration of the fingers, toes, and occasionally other areas.This condition may also cause nails to become brittle with longitudinal ridges.aynaud's disease, or Primary Raynaud's, is diagnosed if the symptoms are idiopathic, that is, if they occur by themselves and not in association with other diseases. Some refer to Primary Raynaud's disease as being allergic to coldness.