Other Conditions With Symptoms Similar to Chronic Fatigue Syndrome
Fatigue can be a symptom of hundreds of medical conditions. All other
possible causes of fatigue will be ruled out before
chronic fatigue syndrome (CFS) is diagnosed. Exams and
tests are used to rule out the most likely causes of fatigue, depending on the
person's medical history and symptoms.
Chronic, persistent fatigue may be a symptom of various conditions,
- Fibromyalgia. Although fibromyalgia and
CFS can have similar symptoms, people who have fibromyalgia tend to have more
muscle pain and more specific tender points than people who have CFS. In
contrast, the main symptom of CFS is overwhelming fatigue. Also, fibromyalgia
is much more common than chronic fatigue syndrome, affecting as many as 5
million people in the United States.1
- Lyme disease.
- Depression or
- Infectious mononucleosis (mono).
- Multiple sclerosis (MS) or
- Sleep apnea.
- Rheumatoid arthritis.
- Infectious diseases, such as
human immunodeficiency virus (HIV)
- Certain types of cancer (lymphoma,
- Neurasthenia, or nervous
exhaustion, a disease marked by intense nervous irritability and weakness.
- Multiple chemical sensitivity disorder, a controversial diagnosis
of an allergy-like sensitivity to an unusually broad range and number of
substances. This condition has not been subjected to rigorous scientific
scrutiny, and there is considerable doubt as to whether it actually
Other possible causes of fatigue include:
- Medicine side effects, or
medicines changed or added too quickly.
- Alcohol or drug
- Too little exercise or excessive exercise
National Institute of Arthritis and Musculoskeletal
and Skin Diseases (NIAMS) (2009). Questions and Answers About Fibromyalgia. Available online:
|Primary Medical Reviewer||Anne C. Poinier, MD - Internal Medicine|
|Specialist Medical Reviewer||Nancy Greenwald, MD - Physical Medicine and Rehabilitation|
|Last Revised||April 22, 2011|