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Are Fibromyalgia and Chronic Fatigue similar?

Chronic Fatigue Syndrome is a condition characterized by debilitating fatigue and recurrent flulike symptoms, such as muscle and joint aches, sore throat, swollen glands, and difficulty thinking.

Fibromyalgia is often marked by widespread muscle pain. Scientists have debated on this and many other similar conditions which share a lot of these symptoms.


Sometimes these get labelled by different specialists depending on where the patient first felt the symptoms or the clinic that they attend. If pins and needles and abnormal sensations are felt first then they may see a neurologist and get a diagnosis of functional neurological disorder. If they see their GP and their chief complaint is fatigue then it could be Chronic Fatigue Syndrome (CFS) and if they see a rheumatologist or pain physician with pain as their chief complaint, it would be a diagnosis of Fibromyalgia.


A recent article on a website compares CFS and FM to Siamese twins - “they were both the same "person" but had two different names, two similar but different personalities.”


Both diagnoses have several features in common: increasing fatigue with exercise, cognitive(concentration and memory) difficulties, muscle pain (or myalgias) and a sleep problem.

Both are frequently associated with other conditions like are irritable bowel syndrome, irritable bladder, jaw pain, migraine and headache.

Both are more common in women. But increasingly more and more men and children are often diagnosed with either one or both before they are 20.

The symptoms are similar for both syndromes, including debilitating fatigue, post-exertional malaise, feverishness, sore throat, headache, joint aches, a feeling of generalized weakness, subjective swelling, non-radicular paresthesias (numbness or tingling that does not follow typical nerve patterns), memory loss, forgetfulness, confusion, irritability, and depressed mood.


Usually CFS is triggered by flulike infections while FM is often got a traumatic trigger ie it can be due to physical or emotional or surgical trauma.

Other differences and similarities are well captured in the table which has been previously published in


Charles Lapp also mentions that there is a chemical called Substance P which is responsible for the transmission of pain and this is elevated in persons with FM (but not CFS); and similarly there is another chemical called RNaseL, which is raised in CFS (but not in FM). This could be one of the reasons to explain why pain is a key symptom in FM, and fatigue and flu like symptoms predominate in CFS.

In terms of treatment and especially exercise, fibromyalgia patients respond to a progressive exercise program but CFS may have worsened symptoms with such a regime and may need to start at a lower level. 


There are patients who may have only fatigue or only pain and they would be called as the “pure” cases but they are a small number and predominantly within a few years, both groups of patients have similar symptoms of pain and fatigue. Charles Lapp concludes that CFS and FM may represent the extreme ends of a spectrum of multisystem disorders characterized by fatigue, pain, and female predominance.



Fibromyalgia information leaflet by Dr Deepak Ravindran, Consultant Pain Medicine Royal Berkshire Hospital

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