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Chronic Fatigue Syndrome Health Center

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Chronic Fatigue Syndrome - Topic Overview

Chronic fatigue syndrome (CFS), sometimes called myalgic encephalomyelitis (ME), is a condition that makes you feel so tired that you can't do all of your normal, daily activities. There are other symptoms too, but being very tired is the main one. Some people have severe fatigue and other symptoms for many years.

CFS is not well understood. Most experts now believe that it is a separate illness with its own set of symptoms. But some doctors don't believe this.

There are no tests for CFS. Because of this, many people have trouble accepting their disease or getting their friends and family to do so. Having people who believe your diagnosis and support you is very important. Having a doctor you can trust is critical.

Your tiredness is real. It's not "in your head." It is your body's reaction to a mix of factors.

Doctors don't know what causes CFS. Sometimes it begins after a viral infection, but there is no proof of any connection. It's likely that a number of factors or triggers come together to cause CFS.

Extreme tiredness, or fatigue, is the main symptom. If you have CFS:

  • You may feel exhausted all or much of the time.
  • You may have problems sleeping. Or you may wake up feeling tired or not rested.
  • It may be harder for you to think clearly, to concentrate, and to remember things.
  • You may also have headaches, muscle and joint pain, a sore throat, and tender glands in your neck or armpits.
  • Your symptoms may flare up after a mental or physical activity that used to be no problem for you. You may feel drained or exhausted.

Depression is common with CFS, and it can make your other symptoms worse.

There are no tests for CFS. Doctors can diagnose it only by ruling out other possible causes of your fatigue. Many other health problems can cause fatigue. Most people with fatigue have something other than chronic fatigue syndrome.

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