Making the Diagnosis
Doctors use two commonly accepted sets of criteria to diagnose chronic fatigue syndrome. Both require that the individual has experienced, for at least six months, unexplained and disabling fatigue that is not relieved by rest. Fatigue is considered unexplained if a thorough physical examination as well as medical testing have excluded other conditions that could cause fatigue. Other criteria necessary to diagnose chronic fatigue syndrome include mental changes such as poor memory, muscle or joint pains, headaches, tender lymph nodes, unrefreshing sleep, and worsening of symptoms after exercise.