The exact cause of chronic fatigue syndrome (CFS) is unknown. Some theories suggest CFS may be due to:
Epstein-Barr virus or human herpes virus-6 (HHV-6); however, no specific virus has been identified as the cause
Inflammation in the nervous system, because of a faulty immune system response
The following may also play a role in the development of CFS:
CFS most commonly occurs in women ages 30 to 50.
Symptoms of CFS are similar to those of the flu and other common viral infections. Symptoms may include muscle aches, headache, and extreme fatigue. However, symptoms of CFS last for 6 months or more. CFS may be similar to fibromyalgia in many cases.
The main symptom of CFS is extreme tiredness, which is:
Lasts at least 6 months
Not relieved by bed rest
Severe enough to keep you from participating in certain activities
Other symptoms include:
Feeling extremely tired for more than 24 hours after exercise that would normally be considered easy
Feeling unrefreshed after sleeping for a proper amount of time
Joint pain, but no swelling or redness
Headaches that differ from those you have had in the past
There is currently no cure for CFS. The goal of treatment is to relieve symptoms. Many people with CFS have depression and other psychological disorders that may improve with treatment.
Treatment includes a combination of the following:
Cognitive-behavioral therapy (CBT) and graded exercise for certain patients
Sleep management techniques
Medicines to reduce pain, discomfort, and fever
Medicines to treat anxiety (anti-anxiety drugs)
Medicines to treat depression (antidepressant drugs)
Some drugs can cause reactions or side effects that are worse than the original symptoms of the disease.
People with CFS are encouraged to maintain active social lives. Mild physical exercise may also be helpful. Your health care team will help you figure out how much activity you can do, and how to slowly increase your activity. Tips include:
Avoiding doing too much on days when you feel tired
Balancing your time between activity, rest, and sleep
Breaking big tasks into smaller, more manageable ones
Spreading out more challenging tasks throughout the week
Relaxation and stress-reduction techniques can help manage chronic pain and fatigue. They are not used as the primary treatment for CFS. Relaxation techniques include:
Deep breathing exercises
Muscle relaxation techniques
Some people may benefit from taking part in a chronic fatigue syndrome support group.
The long-term outlook for patients with CFS varies. It is hard to predict when symptoms first start. Some patients completely recover after 6 months to a year.
Some people never feel like they did before they developed CFS. Studies suggest that you are more likely to get better if you receive extensive rehabilitation.
Inability to participate in work and social activities, which can lead to isolation
Side effects from medication or treatments
When to Contact a Medical Professional
Call your health care provider if you have severe fatigue, with or without other symptoms of this disorder. Other more serious disorders can cause similar symptoms and should be ruled out.
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Gordon A. Starkebaum, MD, Professor of Medicine, Division of Rheumatology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.