Symptoms of chronic fatigue syndrome (CFS) may occur suddenly after you have a cold, bronchitis, hepatitis, or an intestinal infection. Symptoms may follow a bout of infectious mononucleosis, which is caused by a virus that temporarily saps your energy. CFS can also begin after a period of high stress. Sometimes it develops more gradually, with no clear illness or other event noted as a starting point.
Unlike flu symptoms that usually go away in a few days or weeks, symptoms of CFS persist or recur in cycles for at least 6 months in at least 50% of the time. CFS symptoms vary from person to person. The guidelines for diagnosing CFS include, in addition to a 6-month history of fatigue that is not relieved with bed rest, at least 4 of the following 8 symptoms:
In addition to the eight diagnostic symptoms, patients with CFS can also suffer from:
Chronic fatigue syndrome: causes & risk factors. American Academy of Family Physicians Family Doctor website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/chronic-fatigue-syndrome/causes-risk-factors.html. Updated May 2017. Accessed June 1, 2017.
Chronic fatigue syndrome symptoms. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/cfs/symptoms/index.html. Updated May 14, 2012. Accessed June 1, 2017.
Chronic fatigue syndrome. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T115094/Chronic-fatigue-syndrome. Updated February 10, 2017. Accessed May 31, 2017.
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Last reviewed May 2017 by James P. Cornell, MD Last Updated: 12/20/2014