Causes

Dopamine, for example, may act as a stimulant of the migraine process. Some evidence suggests that certain genetic factors make people over-sensitive to the effects of dopamine, which include nerve cell excitation. Such nerve-cell over-activity could trigger the events in the brain leading to migraine. The prodromal symptoms (mood changes, yawning, drowsiness), for example, have been associated with increased dopamine activity. Dopamine receptors are also involved in regulation of blood flow in the brain.

Reduced Magnesium Levels. Magnesium deficiencies have been observed in people with both tension-type and migraine headaches. Researchers have noted a drop in magnesium levels before or during a migraine attack. Magnesium plays a role in nerve cell function. Reduced levels could be a destabilizing factor, causing the nerves in the brain to misfire, possibly even accounting for the auras that many sufferers experience.

Nitric Oxide. Other research suggests that over-excitable neurons release nitric oxide, a small molecular messenger that may be important in triggering in most primary headaches (tension-type, cluster, and migraines). Elevated levels have been observed in blood cells of patients with tension-type headache. Some evidence suggests that the release of this molecule in blood vessels may activate nerve pathways in the brain, muscles, or elsewhere and increase pain.

Estrogen Fluctuations in Women. Tension-type headaches and migraine headaches are slightly more common in females during adolescence and adulthood. Most likely hormone fluctuations, rather than whether levels are elevated or low, trigger headaches. Some research suggests that fluctuations in estrogen levels may impact levels of serotonin and other pain-modulating substances that affect these headaches.

Inflammation in the Maxillary Nerve. Early studies suggest that some chronic tension-type and migraine headaches may be caused by inflammation in the nerve that runs behind the cheekbone (the maxillary nerve) -- not around the covering of the brain. In fact, some work using ice water for reducing swelling in areas of the gums above the last upper molars has relieved some severe migraine and tension-type headaches.