Raynaud's PhenomenonRaynaud's phenomenon is a problem with blood flow. Your body doesn't send enough blood to your hands and feet, so they feel very cold and numb. In most cases, this lasts for a short time when your body overreacts to cold temperatures.There are two kinds of Raynaud's phenomenon. Primary Raynaud's is also known as Raynaud's disease. It occurs on its own and is the most common form. Secondary Raynaud's is also called Raynaud's syndrome. It most often forms as part of another disease.People may not talk to a doctor about symptoms of Raynaud's. For most people, it is more of a nuisance than a disability.What causes Raynaud's phenomenon?Primary Raynaud's has no known cause. Secondary Raynaud's may be a symptom of another disease such as lupus, scleroderma, rheumatoid arthritis, or atherosclerosis. Taking certain medicines, using vibrating power tools for several years, smoking, or having frostbite may also cause Raynaud's.Certain things, such as stress and taking certain medicines, can trigger an attack. But the most common trigger is exposure to cold. In the cold, it's normal for the body to narrow the small blood vessels to the skin and to open the blood vessels to the inside parts of the body to keep the body warm. But with Raynaud's, the body overreacts and restricts blood flow through the small vessels to the skin more than necessary.An attack most often lasts only a few minutes. But in some cases it may last more than an hour.Treatment;If you have secondary Raynaud's that is caused by another disease, your doctor can treat that disease. This may relieve your symptoms.There is no cure for primary Raynaud's, but you may be able to control it by avoiding the things that trigger it. These triggers include cold temperatures, stress, smoking, caffeine & cold medicines.