Serotonin is a chemical necessary for communication between nerve cells. It can cause narrowing of blood vessels throughout the body. When serotonin or estrogen levels change, the result for some is a migraine. The narrowing in blood vessels causes the brain to produce a reaction to trigger the electrical system.  This electrical activity causes a change in blood flow to the brain, which in turn affects the brain's nerves, causing pain.

Stress at work or home can cause migraines, Bright or flashing lights can induce migraines, as can loud sounds. Strong smells — such as perfume, paint thinner, secondhand smoke and others — trigger migraines in some people.

Migraines can be treated with Ergot alkaloids: If it is an acute migraine= ergotamide, if migraine is long lasting = prophylaxis=methysergide that cause vasoconstriction. Autocoids prophylaxis=flunarizine.