Migraine

Definition:

A type of headache. See classical migraine (migraine with an aura); common migraine (migraine without an aura); mixed tension migraine (has features of both migraines and tension headache).

Causes, incidence, and risk factors:

Migraines may occur when blood vessels of the head and neck spasm or constrict, which decreases blood flow, causing symptoms other than headache. Classical migraine is preceded by an aura, a group of symptoms that indicates a pending migraine headache. Common migraine is not.

Migraine headaches affect about 6 out of 100 people. They are a common type of chronic headache. Migraines most commonly occur in women and usually begin between the ages of 10 and 46. They appear to run in families in some cases. Classical migraine accounts for about one-sixth of all migraines. Common migraine and other (rare) forms account for the rest.