migraine (mĪˈgrān) [key], headache characterized by recurrent attacks of severe pain, usually on one side of the head. It may be preceded by flashes or spots before the eyes or a ringing in the ears, and accompanied by double vision, nausea, vomiting, or dizziness. The attacks vary in frequency from daily occurrences to one every few years.
Migraine affects women three times as often as men and is frequently inherited. Many disturbances, such as allergy, temporary swelling of the brain, and endocrine disturbances, have been suspected of causing some varieties of the disorder. Although the exact cause is unknown, evidence suggests a genetically transmitted functional disturbance of cranial circulation. The pain is believed to be associated with constriction followed by dilation of blood vessels leading to and within the brain.
Untreated attacks may last for many hours. Mild attacks are often relieved by common sedatives such as aspirin or codeine. Severe attacks may be treated with any of a variety of drugs, including a group called triptans, by injection or in the form of pills or nasal sprays. Certain beta-blockers, antiepileptic drugs, or tricyclic antidepressants may reduce the recurrence of migraines in some patients. Biofeedback is used in training people to recognize the warning symptoms and to practice control over the vascular dilation that initiates attacks.