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(hed′āk″) ABBR: HA. Pain felt in the forehead, eyes, jaws, temples, scalp, skull, occiput, or neck. Headache is exceptionally common; it affects almost everyone at some time. From a clinical perspective, benign HA must be distinguished from a potentially life-threatening HA. Types of benign HA include tension, migraine, cluster, sinus, and environmentally induced (such as an ice cream HA HA or a caffeine-withdrawal HA HA). A life-threatening HA may be caused by rupture of an intracranial aneurysm, subarachnoid hemorrhage, hemorrhagic stroke, cranial trauma, encephalitis, meningitis, brain tumors, or brain abscesses. SYN: cephalalgia. SEE: migraine.

Typically, benign HAs have a recurrent or chronic history familiar to the patient. The tension HA sufferer, for example, develops bandlike pressure around the head at the end of a difficult or stressful day. The onset of the HA is gradual and progressively worsens but is usually not severe or intense.

The migraine HA sufferer also typically has a history of recurrent HA, often dating back to childhood. Migraine HA is often of rapid onset, unilateral, throbbing, or beating in character. It may be preceded by teichopsia or scotoma and be associated with nausea, vomiting, or even transient neurological deficits, such as hemibody weakness. The HA may be triggered by eating chocolate, monosodium glutamate, or some cheeses; drinking alcohol; or taking certain medications, such as the hormone estrogen. By contrast, an HA that is life-threatening may have some of the following hallmarks: (1) first, or the worst, HA a patient has ever suffered, i.e., subarachnoid hemorrhage should be suspected; (2) first occurrence in a patient with a history of cancer (metastatic tumor); (3) accompanying fever, stiff neck, or photophobia (meningitis, intracranial hemorrhage); (4) associated loss of consciousness or severely altered mental status (intracerebral hemorrhage, brain embolism, encephalitis, meningitis); (5) associated neurological deficits that do not quickly resolve (intracerebral hemorrhage, brain embolism, brain abscesses); (6) occurrence in a patient with recent head trauma (hemorrhage, carotid artery dissection) or a history of recent foreign travel (neurocysticercosis; falciparum malaria); and (7) occurrence in a patient with acquired immunodeficiency syndrome (cryptococcal meningitis, Toxoplasma gondii, central nervous system lymphoma).

Only a few examples are given here. Almost any disturbance of body function may cause HA, including sunstroke, motion sickness, insomnia, altitude sickness, spinal puncture, alcohol withdrawal, prolonged fasting, exposure to loud noise, menstruation, psychological stressors, or new medications, e.g., nitrates.

TREATMENT: Mild HA often responds to rest, massage, acetaminophen, or listening to relaxing music. Moderate HA typically requires nonsteroidal anti-inflammatory drug (NSAID) therapy. Caffeine helps ameliorate many mild to moderate HAs. Antiemetics (e.g., prochlorperazine, metoclopramide) help relieve moderate to severe HAs, esp. those accompanied by nausea; ergotamines and the triptan drugs are particularly suited to treating migraines. Cluster HAs often resolve after treatment with corticosteroids or high-flow oxygen. The HA of temporal arteritis also responds to high-dose steroids, but these agents must be continued for months ...

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