Raynaud’s phenomenon is a condition in which cold temperatures or strong emotions cause blood vessel spasms that block blood flow to the fingers, toes, ears, and nose.

Raynaud's phenomenon can be associated with other conditions. This is called secondary Reynaud's phenomenon. Most people with the condition are over age 30.

Common causes are:

• Diseases of the arteries, such as atherosclerosis and buerger's disease
• Drugs that cause narrowing of arteries, such as amphetamines, certain types of beta-blockers, some cancer drugs, ergot compounds, and methysergide
• Arthritis and autoimmune conditions, such as scleroderma, Sjogren syndrome, rheumatoid arthritis, and systemic lupus erythematosus
• Repeated injury, particularly from vibrations such as those caused by typing or playing the piano
• Smoking
• Frostbite
• Thoracic outlet syndrome

Raynaud's phenomenon also occurs without another disease, medication, or cause. This is called primary Raynaud's phenomenon. It is most often seen in people younger than age 30.