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migraine





A migraine is a severe type of headache, which may last from 2 hours to 2 days. People who get migraines often describe the pain as pulsing or throbbing in one area of the head. During migraines, people are very sensitive to light and sound. They may also become nauseated and vomit. A sufferer may experience only a single attack; more commonly, he or she has recurrent attacks at varying intervals.


Causes and incidence of migraine

Migraine occurs in at least 10 percent of the population and is three times more common in women than in men. It may affect children as young as three years old; 60 percent of migraine sufferers have their first attack before the age of 20. It is extremely rare for migraine to appear for the first time after the age of 50.

Some people can tell when they are about to have a migraine because they see flashing lights or zigzag lines or they temporarily lose their vision.

Many things can trigger a migraine, including:
  • Anxiety
  • Stress
  • Lack of food or sleep
  • Exposure to light
  • Hormonal changes (in women)
Doctors used to believe migraines were linked to the opening and narrowing of blood vessels in the head. Now they believe the cause is related to genes that control the activity of some brain cells. Medicines can help prevent migraine attacks or help relieve symptoms of attacks when they happen. For many people, treatments to relieve stress can also help.


Types of migraine

There are two types of migraine: common and classical. In common migraine, the pain of the headache develops slowly, sometimes mounting to a throbbing pain that is made worse by the slightest movement or noise. The pain is often, but not always, on only one side of the head and usually occurs with nausea and vomiting. Many sufferers, particularly children, recover after they have vomited.

Classical migraine is comparatively rare. The headache is preceded by a slowly expanding area of blindness surrounded by a sparkling edge that increases to involve up to one half of the field of vision in each eye. The blindness clears up after about 20 minutes and is often followed by a severe one-sided headache with nausea, vomiting, and sensitivity to light. Other temporary neurological symptoms, such as weakness in one half of the body, may occur.


Diagnosis

Special tests are rarely necessary. The doctor can usually make a diagnosis from the patient's history and a physical exam. If there are accompanying persistent symptoms (such as tingling in a limb) or if the type of headache changes or becomes more severe, a full neurological examination may be carried out to exclude the possibility of a serious condition.


Treatment of migraine

If migraine attacks occur less frequently than once a month, treatment of the acute attack is all that is required. If the attacks are more frequent, preventative treatment may be necessary. The simplest form of prevention is to avoid known triggers; keeping a diary can help a sufferer to pinpoint what triggers his or her attacks.

The best treatment for an acute migraine attack is aspirin or paracetamol plus an antiemetic drug (often provided in suppository form). If this combination is not effective, ergotamine may also be prescribed. Certain ergotamine preparations may help prevent an attack if taken in the early phases before the headache begins. Most people find that they recover more quickly if they can then sleep in a darkened room.

In cases where migraine attacks happen more often than once a month, prophylactic drugs, such as beta blockers and calcium channel blockers may be prescribed.


Related category

   • HEALTH AND DISEASE

Source: National Institute of Neurological Disorders and Stroke