Migraine (from the Greek words hemi, meaning half, and kranion, meaning skull) 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 typical migraine headache is unilateral (affecting one half of the head) and pulsating in nature and lasting from 4 to 72 hours; symptoms include nausea, vomiting, photophobia (increased sensitivity to light), 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 aura—transient visual, sensory, language, or motor disturbances signalling that the migraine will soon occur...