A migraine headache is a form of vascular headache. Migraine headache is caused by a combination of vasodilatation (enlargement of blood vessels) and the release of chemicals from nerve fibers that coil around the blood vessels.

During a migraine attack, the temporal artery enlarges; the temporal artery is an artery that lies on the outside of the skull just under the skin of the temple.

Enlargement of the temporal artery, stretches the nerves that coil around the artery and cause the nerves to release chemicals.

The chemicals cause inflammation, pain, and further enlargement of the artery. The increasing enlargement of the artery magnifies the pain.

It is important to prevent migraine headaches by avoiding factors that cause the headaches, and preventing headaches with medications (prophylactic medications).

The best methods thought to overcome or prevent these types of headaches are to reduce the frequency of headaches.

A migraine trigger is any factor that causes a headache in individuals who are prone to develop headaches. Only a small proportion of migraine sufferers, however, clearly can identify triggers.

Examples of triggers include stress, sleep disturbances, fasting, hormones, bright or flickering lights, odors, cigarette smoke, alcohol, aged cheeses, chocolate, monosodium glutamate, nitrites, aspartame, and caffeine.

For some women, the decline in the blood level of estrogen during the onset of menstruation is a trigger for migraine headaches. The interval between exposure to this cause or a trigger and the onset of headache varies from hours to two days.

Exposure to a trigger does not always lead to a headache. Conversely, avoidance of triggers cannot completely prevent headaches.

Different migraine sufferers respond to different triggers, and any one trigger will not induce a headache in every person who has migraine headaches.

Prevention

Disturbances such as sleep deprivation, too much sleep, poor quality of sleep, and frequent awakening at night are associated with both migraine and tension headaches, whereas improved sleep habits have been shown to reduce the frequency of migraine headaches. Sleep also shortens the duration of migraine headaches.

Fasting possibly may precipitate migraine headaches by causing the release of stress-related hormones and lowering blood sugar. Therefore, migraine sufferers should avoid prolonged fasting.

Bright lights and other high intensity visual stimuli can cause headaches in healthy people as well as patients with migraine headaches, but migraine patients seem to have a lower than normal threshold for light-induced pain.

Sunlight, television, and flashing lights all precipitate migraine headaches.

Caffeine is contained in many food products such as cola, tea, chocolates, and coffee. Caffeine in low doses can increase alertness and energy, but caffeine in high doses can cause insomnia, irritability, anxiety, and headaches.

The over use of caffeine containing analgesics causes rebound headaches.

Furthermore, individuals who consume high levels of caffeine regularly are more prone to develop withdrawal headaches when caffeine is stopped abruptly.

Some women who suffer from migraine headaches experience more headaches around the time of their menstrual periods. Other women experience migraine headaches only during the menstrual period.

The term menstrual migraine is used mainly to describe migraines that occur in women who have almost all of their headaches from two days before to one day after their menstrual periods.

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