Centers for Disease
Control and Prevention Case Definition of Chronic Fatigue
Syndrome*
CFS is a syndrome characterized by fatigue that
is:
Medically unexplained
Of new onset
Of at least
six months' duration
Not the result
of ongoing exertion
Not substantially
relieved by rest
Causes a substantial
reduction in previous levels of occupational, educational, social or personal activities
In addition, there
must be four or more of the following symptoms:
Impaired memory
or concentration
Sore throat
Tender neck
(cervical) or armpit (axillary) lymph nodes
Muscle pain
(myalgia)
Headaches of
a new type, pattern or severity
Unrefreshing
sleep
Post-exertiional
malaise (lasting more than 24 hours)
Multi-joint pain (arthralgia without swelling or redness)
Conditions that
would exclude a diagnosis of CFS include other medical disorders known to cause fatigue, major depressive
illness, medication that causes fatigue as a side effect, and alcohol or substance abuse.
*Fukuda
et al, The chronic fatigue syndrome: a comprehensive approach to its definition and study, Ann Intern
Med., 1994; 121:953-59.
