The cluster headache is described separately. These are fairly common headaches that affect up to 28 million people in the United States, almost three-fourths women. They cause significant economic loss as measured in time away from work. Cause The specific cause of migraine headache is unknown. It used to be thought that the problem was primarily a vascular problem involving the blood vessels of the head.
Much research still remains to be done.
The symptoms of a migraine depend on the type of migraine. Although there is variability in the symptoms, the two types are quite distinct. Migraine without aura is characterized by a recurring headache that is located on one side of the head and lasts between 4 and 72 hours. The headache is usually throbbing and may be moderate to severe. Activity usually makes the headache worse.