Migraine is an episodic primary headache disorder. Symptoms usually last for 4 to 72 h and may be mild to severe. Pain is often unilateral,pulsatile, throbbing, worse with exertion, and accompanied by symptoms such as nausea and photophobia sensitivity to light, sound, or odors. Auras occur in about 25% of patients, usually just before but sometimes after the headache. Diagnosis of migraine is clinical.