Migraine - Migraine headache

Migraine is a severe headache caused by changes in the calibre of the cranial blood vessels. Migraine is the second most common cause of headache, and the leading cause of disabling headache. It is most common in young women.

Although the exact cause is unknown, it is typically triggered by external stimuli that activate the trigeminal nerve, causing the release of nerve transmitters capable of constricting the blood vessels of the nerve itself and deep within the brain. 

It manifests as a severe headache, usually on one side and with pulsating characteristics. It is usually accompanied by nausea, photophobia, dizziness and other neurological symptoms. 

Sometimes before the pain the person has sensations (prodromes) that indicate that a new attack is about to begin: yawning, euphoria, irritability, inattention, pallor and a compulsive desire to eat sweet foods. Shortly afterwards, there may be an aura phase with visual disturbances, loss of sensation and motor impairment. Finally, after the pain phase, there may be general malaise, tiredness, lack of concentration and drowsiness.

Diagnosis is clinical, by interrogation and physical examination. In severe cases, a scan may be requested to differentiate it from a cerebral vascular accident.