Functional somatic syndrome

Functional somatic syndromes (or FSS) are groups of physical symptoms that occur together, with no known physical cause. The lack of a clear physical basis for the illness can lead to assumptions that it is a psychosomatic illness. The term "functional somatic syndromes" is sometimes used to refer to physical illnesses which are not fully understood, even when these illnesses are classified as specific diseases rather than as illnesses of unknown origin, for example chronic fatigue syndrome, fibromyalgia syndrome and irritable bowel syndrome may be referred to as "functional somatic syndromes" by proponents of the biopsychosocial model of understanding illness.

Lumping illnesses together
Functional somatic syndromes is a term used to lump different illness together on the basis on overlapping symptoms, despite their separate diagnostic criteria. Lumping distinct disorders together, and regarding all as medically unexplained physical symptoms is an approach that has been criticized by unscientific and lacking validity.

Notable studies

 * 1999, Functional somatic syndromes: one or many? (Abstract)


 * 2001, Medically unexplained symptoms: an epidemiological study in seven specialities (Abstract)

Letters, articles and talks

 * 2000, Functional somatic syndromes (Full text)
 * 2013, Disease-modifying therapies for nonrelapsing multiple sclerosis: Absence of evidence does not constitute evidence of absence