A migraine headache is a vascular headache associated with changes in the size of the arteries within and outside of the brain.

Who Gets Migraines?
The National Headache Foundation estimates that 28 million Americans suffer from migraines. More women than men get migraines and a quarter of all women with migraines suffer four or more attacks a month; 35% experience 1-4 severe attacks a month, and 40% experience one or less than one severe attack a month. Each migraine can last from four hours to three days. Occasionally, it will last longer.

What Causes Migraine Headaches?
The exact causes of migraine headaches are unknown, but the headaches are linked to changes in the brain as well as to genetic causes. Experts believe that migraines may be caused by inherited abnormalities in certain areas of the brain. People with migraines may inherit the tendency to be affected by certain migraine triggers including fatigue, bright lights, and weather changes.

Additional possible triggers include:

* Emotional stress
* Sensitivity to specific chemicals and preservatives in food. Certain foods, beverages and food additives may be responsible for triggering up to 30% of migraines. Aged cheeses, alcoholic beverages, nitrates (sometimes found in processed meats), and monosodium glutamate (MSG) have been linked to migraines.
* Caffeine. Excessive caffeine consumption or withdrawal from caffeine can cause headaches when the caffeine level abruptly drops. The blood vessels seem to become sensitized to caffeine. When caffeine is not ingested, a headache may occur. Caffeine itself is often helpful in treating acute migraine attacks.
* Changing weather conditions. Storm fronts, barometric pressure changes, strong winds, and altitude changes have been linked to migraines.
* Menstrual periods
* Tension
* Excessive fatigue
* Skipping meals
* Changes in normal sleep patterns

What Are the Symptoms of Migraines?
The pain of a migraine can be described as a pounding or throbbing. The headache often begins as a dull ache and develops into a throbbing pain. The pain is usually aggravated by physical activity. Migraine pain can be classified as mild, moderate, or severe.

Some other associated symptoms of migraine headaches include: * Sensitivity to light, noise and odors * Nausea and vomiting, stomach upset, abdominal pain * Loss of appetite * Sensations of being very warm or cold * Paleness * Fatigue * Dizziness * Blurred vision

Types of Migraines
There are several types of migraine headaches, including:

* Migraine with aura (classic migraine): This type is usually preceded by an aura. Most often, an aura is a visual disturbance (outlines of lights or jagged light images). This type of migraine usually is much worse than a common migraine.

* Migraine without aura (common migraine): This type accounts for 80% of migraine headaches. There is no aura before a common migraine.

* Status migrainosus: This is the term used to describe a long-lasting migraine that does not go away on its own.

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