Migraine is a chronic neurological disorder characterized by moderate to severe headaches, and nausea. It is about three times more common in women than in men. The word derives from the Greek á¼¡Î¼Î¹ÎºÏÎ±Î½Î¯Î± (hemikrania), "pain on one side of the head", from á¼¡Î¼Î¹- (hemi-), "half", and ÎºÏÎ±Î½Î¯Î¿Î½ (kranion), "skull".
The typical migraine headache is unilateral (affecting one half of the head) and pulsating in nature and lasting from two to 72 hours; symptoms include nausea, vomiting, photophobia (increased sensitivity to light) and phonophobia (increased sensitivity to sound); the symptoms are generally aggravated by routine activity. Approximately one-third of people who suffer from migraine headaches perceive an auraâ€”transient visual, sensory, language, or motor disturbances signaling the migraine will soon occur.
Initial treatment is with analgesics for the headache, an antiemetic for the nausea, and the avoidance of triggers. The cause of migraine headache is unknown; the most supported theory is that it is related to hyperexcitability of the cerebral cortex and/or abnormal control of pain neurons in the trigeminal nucleus of the brainstem.
Studies of twins indicate a 60- to 65-percent genetic influence upon their propensity to develop migraine headaches. Moreover, fluctuating hormone levels indicate a migraine relation: 75 percent of adult patients are women, although migraine affects approximately equal numbers of prepubescent boys and girls. Propensity to migraine headache sometimes disappears during pregnancy, but in some women, migraines may become more frequent.