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Chronic fatigue syndrome


* Not a rare disease
Other Names for this Disease
  • Myalgic encephalomyelitis
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Chronic fatigue syndrome is a condition that causes extreme, long-lasting fatigue which can limit the ability to participate in ordinary, daily activities.[1] It generally occurs in young adults between the ages of 20 and 40.[2] The main symptom of this condition is disabling fatigue that does not improve with rest.[2] Other signs and symptoms may include muscle pain; joint pain; concentration and memory problems; headaches; sleep problems; fever; sore throat; and/or tender lymph nodes.[1][2] The exact cause of chronic fatigue syndrome is not known, but it has been proposed that infectious agents, immune system impairment and/or hormonal system deregulation may be involved.[2] There is no cure for this condition; the goal of treatment is to improve symptoms. Medications may be used to treat pain, sleep disorders and other associated problems.[1]
Last updated: 10/14/2013


  1. Chronic fatigue syndrome. MedlinePlus. Accessed 5/5/2009.
  2. Pierre-Yves Hatron. Chronic Fatigue Syndrome. Orphanet. April 2009; Accessed 10/14/2013.
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Basic Information

  • The Mayo Foundation for Medical Education and Research also provides information about chronic fatigue syndrome. Click on the link above to view this information page.
  • You can obtain information on this topic from the Centers for Disease Control and Prevention (CDC). The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.
  • The Lab Tests Online Web site provides additional information on chronic fatigue syndrome. This information can be viewed by clicking on "Lab Tests Online."
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The Merck Manuals Online Medical Library provides information on this condition. Click on the link to view the information.
  • The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.

In Depth Information

  • Medscape Reference provides information on this topic. Click on the link to view this information. You may need to register to view the medical textbook, but registration is free.
  • MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs.  Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Chronic fatigue syndrome. Click on the link to view a sample search on this topic.