Migraine

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Migraine, severe headache that occurs periodically and is sometimes confined to only one side of the head. A migraine is characterized by intense, throbbing, often blinding pain, and one or more of the following symptoms: sensitivity to light, nausea, vomiting, chills, facial swelling, tenderness of the scalp, sweating, frequent urination, irritability, visual hallucinations, and malaise. The headache may be preceded by a warning sensation, known as an aura, that may include flashes or patterns before the eyes, illusory tastes or odors, dizziness, tingling, or numbness.

At the onset of a migraine headache, blood vessels within the head constrict, causing a decrease in blood flow to the surface of the brain. Swelling of blood vessels in the head and scalp then sets off a chain of reactions that result in the headache. Among the biochemical changes associated with migraines are a reduced level of the neurotransmitter serotonin as well as an insufficient supply of enkephalins, the brain’s pain-relieving chemicals.

Hormonal level changes (such as those experienced by women during menopause or menstruation), endocrine imbalances, and stress due to anything from overwork to loud noises are considered precipitating factors of migraine headaches in susceptible people. Other factors that may trigger attacks include allergies, excess carbohydrates in the diet, foods rich in the trace element iodine, and alcoholic beverages.

Several treatments have been successful in helping migraine sufferers. These include medications such as sumatriptan and ergotamine tartrate, both of which shrink swollen blood vessels, thereby aborting the acute phase of a migraine attack; and propranolol, which stabilizes blood vessel tone and helps prevent subsequent attacks. Other drugs often prescribed to migraine sufferers are amitriptyline, phenelzine, and verapamil. Biofeedback techniques have also proven useful.

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