Symptoms and Diagnosis of CFS

CFS is related to fibromyalgia in that fatigue is a large component of both conditions. While pain is the primary symptom in fibromyalgia, the major symptom of CFS is overwhelming fatigue. People with CFS may experience pain as well, but the symptom that most affects them is fatigue.

In order to be diagnosed with chronic fatigue, fatigue symptoms should be present for at least 6 months to a year. The fatigue cannot be explained by other conditions. Often fatigue follows an infection, and the patient never fully recovers. They continue to feel tired and “run down” after the infection is gone.

Cognitive Symptoms

People suffering from CFS may experience “verbal dyslexia”, or difficulty in finding the right words when they are speaking. They often suffer from poor short term memory, but their long term memory is left intact. Problems with short term memory may be due to overwhelming fatigue or another unknown factor.

Postexertional Fatigue

Postexertional fatigue is a term used to describe exhaustion following any form of exertion or exercise. Climbing a flight of stairs may be difficult if you suffer from CFS, where the activity was a simple one before CFS.

Fatigue Despite Adequate Rest

People with CFS typically sleep long hours but awaken feeling just as tired as when they went to bed. Sleep is unrefreshing.This fatigue often interferes with normal activities, and some people with CFS are unable to work due to fatigue.


CFS in itself does not cause depression, but many people with CFS become depressed due to their inability to engage in normal activities. Depression is common and should not be downplayed.


The diagnosis of CFS is one of exclusion. There are no laboratory tests that can rule CFS in or out as a diagnosis; rather, the diagnosis of CFS is made when all other possibilities for symptoms have been ruled out. Conditions that share symptoms of CFS include cancers, AIDS, thyroid disease, blood disorders, kidney disease, Lyme disease, and liver disease.

If you suffer from chronic fatigue, you should visit your doctor so that the cause of your fatigue can be investigated. Because fatigue is such a subjective symptom, be prepared to answer many questions about your work, lifestyle, the onset of symptoms and your past medical history. Chronic fatigue can be caused by many serious conditions, so it is important that you see a doctor if fatigue persists longer than a few weeks.


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Fibromyalgia is a prevalent condition that affects many people in the United States. Approximately 3.7 million Americans have Fibromyalgia. That is 1 in every 73 people.

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