Skip to Main Content
Chronic fatigue syndrome refers to severe, continued tiredness (fatigue). It is not relieved by rest and is not directly caused by other medical conditions.
CFS; Fatigue - chronic; Immune dysfunction syndrome; Myalgic encephalomyelitis (ME)
The exact cause of chronic fatigue syndrome (CFS) is unknown. Some theories suggest CFS may be due to:
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:
Other symptoms include:
The Centers for Disease Control (CDC) describes CFS as a distinct disorder with specific symptoms and physical signs. Diagnosis is based on ruling out other possible causes.
Your health care provider will try to rule out other possible causes of fatigue, including:
A diagnosis of CFS must include:
There are no specific tests to confirm the diagnosis of CFS. However, there have been reports of CFS patients having abnormal results on the following tests:
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:
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:
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:
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.
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.
Cush JJ, Dao KH. Polyarticular arthritis. In: Firestein GS, Budd RC, Gabriel SE, et al, eds. Kelley's Textbook of Rheumatology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2012:chap 42.
Bennett RM. Fibromyalgia and chronic fatigue syndrome. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 282.
Engleberg NC. Chronic fatigue syndrome. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 131.
Nijs J, Roussel N, Van Oosterwijck J, De Kooning M, Ickmans K, Struyf F, et al. Fear of movement and avoidance behaviour toward physical activity in chronic-fatigue syndrome and fibromyalgia: state of the art and implications for clinical practice. Clin Rheumatol. 2013;32(8):1121-9.