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Migraines and Headaches

Migraines are painful headaches often accompanied by nausea, vomiting, and sensitivity to light.

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 one to four 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 Migraines?

The exact causes of migraines are unknown, although they are related to changes in the brain as well as to genetic causes. People with migraines may inherit the tendency to be affected by certain migraine triggers, such as fatigue, bright lights, weather changes, and others.

For many years, scientists believed that migraines were linked to expanding and constricting blood vessels on the brain's surface. However, it is now believed that migraines are caused by inherited abnormalities in certain areas of the brain.

There is a migraine "pain center" or generator in the brain. A migraine begins when hyperactive nerve cells send out impulses to the blood vessels, causing them to clamp down or constrict, followed by dilation (expanding) and the release of prostaglandins, serotonin, and other inflammatory substances that cause the pulsation to be painful.

What Triggers a Migraine?

Many migraines seem to be triggered by external factors. Possible triggers include:

  • Emotional stress. This is one of the most common triggers of migraine headache. Migraine sufferers are generally highly affected by stressful events. During stressful events, certain chemicals in the brain are released to combat the situation (known as the "flight or fight" response). The release of these chemicals can provoke vascular changes that can cause a migraine. Repressed emotions surrounding stress, such as anxiety, worry, excitement, and fatigue can increase muscle tension and dilated blood vessels can intensify the severity of the migraine.
  • Sensitivity to specific chemicals and preservatives in foods. Certain foods and beverages, such as aged cheese, alcoholic beverages, and food additives such as nitrates (in pepperoni, hot dogs, luncheon meats) and monosodium glutamate (MSG, commonly found in Chinese food) may be responsible for triggering up to 30% of 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, and when caffeine is not ingested, a headache may occur. Caffeine itself is often helpful in treating acute migraine attacks.
  • Changing weather conditions. Storm fronts, changes in barometric pressure, strong winds, or changes in altitude can all trigger a migraine.
  • Menstrual periods
  • Excessive fatigue
  • Skipping meals
  • Changes in normal sleep pattern

 

Migraines and Associated Conditions

There are some medical conditions that are more commonly associated with migraines, including:

  • Asthma
  • Chronic fatigue syndrome
  • Hypertension
  • Raynaud's phenomenon (occurs when blood vessels narrow causing pain and discoloration usually in the fingers)
  • Stroke
  • Sleep Disorders

 

WebMD Medical Reference

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