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Chronic Fatigue Syndrome

General Information

Chronic fatigue syndrome (CFS) is an illness consisting of a complex of related symptoms. The most characteristic symptom is debilitating fatigue that persists for several months.

Chronic fatigue syndrome fact sheet, P-42038

For more information, go to the Centers for Disease Control and Prevention (CDC)


  • Greatly lowered ability to do activities that were usual before getting sick. This drop in activity level happens along with fatigue and must last six months or longer. 
  • Worsening of symptoms after physical or mental activity that would not have caused a problem before getting sick.
  • Sleep problems. People with Chronic Fatigue Syndrome may not feel better or less tired, even after a full night of sleep. Some people may have problems falling asleep or staying asleep.
  • Pain – The type of pain, where it occurs, and how bad it is varies a lot. The pain people with Chronic Fatigue Syndrome feel is not caused by an injury. The most common types of pain are:
    • Muscle pain and aches
    • Joint pain without swelling or redness
    • Headaches, either new or worsening
  • Some people with Chronic Fatigue Syndrome may also have:
    • Tender lymph nodes in the neck or armpits
    • A sore throat that happens often
    • Digestive issues, like irritable bowel syndrome
    • Chills and night sweats
    • Allergies and sensitivities to foods, odors, chemicals, light, or noise
    • Muscle weakness
    • Shortness of breath
    • Irregular heartbeat

Provider Information

Information for health care providers from the Centers for Disease Control and Prevention.

Questions about Chronic Fatigue Syndrome? Contact us!
Phone: 608-267-9003 | Fax: 608-267-9009


Last revised April 4, 2024