Chronic fatigue syndrome (CFS) is a debilitating condition characterized by profound tiredness, regardless of how much rest you get.

Having CFS means more than just being tired. The condition often disables sufferers to the point that they can’t take part in everyday activities. For many with CFS, just making it out of bed takes effort. This fatigue persists for months or even years, despite getting plenty of rest and sleep. Work, physical activity, and mental tasks can leave sufferers exhausted for days or weeks.


CFS can occur suddenly and last for years. It affects two to four times more women than men, especially middle-aged women. The cause of CFS isn’t known, nor are there specific tests available to diagnose the condition. But studies have identified differences in the brain and immune and nervous system of those who have it. Genes also may play a role.


CFS diagnosis depends on two criteria:

  • Severity and duration. The severe and chronic tiredness lasts for more than six months and other medical conditions have been ruled out. Several other diseases and conditions can cause fatigue, such as hypothyroidism, sleep apnea and narcolepsy, major depressive disorders, chronic mononucleosis, eating disorders, cancer, autoimmune disease, and reactions to prescribed medications.

  • Number of symptoms. The person has four or more of the symptoms of CFS.


No specific treatments for CFS have proved effective. Vitamin supplements and medications have some benefit for some people with CFS, but many treatments simply ease symptoms.

Treatment for CFS will be determined by your doctor based on your overall health and medical history, the extent of the condition, and your tolerance for specific medications, procedures, or therapies. Treatment may include:

  • Medication, including anti-inflammatories and antidepressants

  • Physical activity

  • Dietary supplements and herbal preparations

  • Psychotherapy and supportive counseling

  • Vitamin B12 supplements

  • Other lifestyle changes, such as preventing overexertion, reducing stress, making diet changes, and doing gentle stretching

Medical Reviewer: [Daphne Pierce-Smith, RN, MSN, FNP, CCRC, Lee Jenkins] Last Annual Review Date: 2009-09-22T00:00:00-06:00 Copyright: © 2000-2010 The StayWell Company, 780 Township Line Road, Yardley, PA 19067. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

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