Raynaud’s phenomenon is a problem that causes decreased blood flow to the fingers. In some cases, it also causes less blood flow to the ears, toes, nipples, knees, or nose. This happens due to spasms of blood vessels in those areas. The spasms happen in response to cold, stress, or emotional upset. Treatment will depend on your symptoms, your age, and your general health. It will also depend on how severe the condition is. There is no cure for Raynaud’s phenomenon, but it can be managed with proper treatment.