The most common patient complaint, headache usually occurs as a symptom of an underlying disorder. Ninety percent of all headaches are vascular, muscle contraction, or a combination; 10% are due to underlying intracranial, systemic, or psychological disorders.
Migraine headaches, probably the most intensively studied, are throbbing, vascular headaches that usually begin to appear in childhood or adolescence and recur throughout adulthood. Affecting up to 10% of Americans, they’re more common in females and have a strong familial incidence.
Most chronic headaches result from tension—muscle contraction—that may be caused by emotional stress, fatigue, menstruation, or environmental stimuli (such as noise, crowds, and bright lights).
Other possible causes include glaucoma; inflammation of the eyes or mucosa of the nasal or paranasal sinuses; diseases of the scalp, teeth, extracranial arteries, or external or middle ear; and muscle spasms of the face, neck, or shoulders.
In addition, headaches may be caused by vasodilators (such as nitrates, alcohol, and histamines), systemic disease, hypoxia, hypertension, head trauma and tumor, intracranial bleeding, abscess, and aneurysm.
The cause of migraine headache is unknown, but a genetic link has been identified. These headaches are associated with constriction and dilation of intracranial and extracranial arteries initiated by neurons in the brainstem. Certain biochemical abnormalities are thought to occur during a migraine attack. They include local leakage of a vasodilator polypeptide called neurokinin through the dilated arteries as an inflammatory response and a decrease in the plasma level of serotonin.
Foods associated with migraine headache include aged or processed cheese and meats, alcoholic beverages (particularly red wine), food additives (such as monosodium glutamate), chocolate- and caffeine-containing foods, and nuts. Changes in the weather pattern, menstrual cycle fluctuations, sleep pattern changes, and too much or too little exercise as well as glaring lights and fatigue can also trigger a migraine headache. In addition, one of the more common causes of a recurring headache is the rebound effect that occurs when the original treatment used to get rid of the headache triggers the next episode (as with narcotics).
Pain may emanate from the pain-sensitive structures of the skin, scalp, muscles, arteries, and