What is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is persistent and crippling fatigue (exhaustion) lasting 6 months or longer. People living with ME/CFS often experience other symptoms, like unrefreshing sleep and muscle aches. The condition is also sometimes called chronic fatigue syndrome.

Doctors do not know what causes ME/CFS, and there is no cure. You may be able to manage symptoms with cognitive-behavioral therapy, exercise, and medications, like antidepressants and sleep aids. The goal of treatment is to make symptoms as manageable as possible to increase your quality of life.

Who is most at risk for getting myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

Women are more likely than men to develop ME/CFS. Young children and teenagers can develop ME/CFS, but the syndrome is much more common in adults.

How common is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

The number of people with ME/CFS is not clear; some estimates put the number at 1 million people in the US, while another estimate is as high as 2.5 million people. Many of these individuals have not received a diagnosis, even though they live with this condition.

What are the symptoms of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

For many people, the symptoms of ME/CFS resemble other diseases, like influenza. Symptoms may come and go over time and may increase or decrease in severity. ME/CFS symptoms vary widely from person to person.

Many of the symptoms of ME/CFS make daily life difficult. These symptoms include:

  • Severe fatigue lasting at least 6 months that does not improve with rest or sleep
  • Difficulty sleeping
  • Flu-like symptoms, including swollen lymph nodes (small immune system structures that filter harmful substances), headaches, and joint pain
  • Cognitive (thinking) difficulties, including attention and memory problems
  • Muscle aches

Less common symptoms of ME/CFS include:

  • Problems with vision
  • Chills
  • Night sweats
  • Irritable bowel, an intestinal condition causing painful bloating, gas, constipation and diarrhea
  • Psychological (mental health) issues, including mood swings, irritability and anxiety
  • Tingling or numbness in the feet, hands or face

For many people, ME/CFS symptoms get worse following physical exercise or strenuous mental exertion. In some cases, orthostatic intolerance (symptoms that get worse if you stand or sit upright) causes dizziness, weakness, and fainting.

What causes myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

Doctors do not know what causes ME/CFS.

Last reviewed by a Cleveland Clinic medical professional on 06/21/2018.


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