Chronic Fatigue Syndrome (CFS) is a debilitating medical condition that is chronic in nature, with unknown causes, and diagnosed by exclusion.  The symptoms are not relieved by rest.  It is a collective term referring to conditions of extreme fatigue with no apparent causes.  It is also known as Chronic Fatigue and Immune Dysfunction Syndrome or Myalfic Encephalomyelitis.  It lasts for 6 months or more and restricts the ability to perform daily activities.  It may also be accompanied by muscle pain, memory degradation, loss of ability to concentrate,  joint pain, sleep disorder, sore throat, tender lymph nodes and headaches.  Since other illnesses can have similar symptoms, CFS is difficult to diagnose.  CFS occurs more with often with women in their 40s and 50s.  Western medicine has no explanation of the causes of CFS.  To date, Western medicine has no recommended or proven treatments.

Way back in the Sui Dynasty 600 AD), Chao Yuanfang 巢元方 wrote a medical compendium called "Origin and Treatment of the Diseases" Zhubing yuanhou lun 諸病源候論.  In it, the symptoms of CFS were documented.  They are categorized into 2 groups: somatic symptoms including fatigue, heaviness, cold knees, puffiness, headaches, joint and muscle pain; and [sychological symptoms such as depression, anxiety and restlessness.  Although these symptoms do not exactly mimic the CDC's (Centre for Disease Control and Prevention) criteria for CFS, they are extremely similar.

TCM (Traditional Chinese medicine) does not recognize CFS as a single health problem, but rather there are a variety of health problems that produce these symptoms.  Mostly, they are related to the deficiencies in the Zangfu (Yin and Yang organ) systems and of Qi and Blood.  They can also be the results of excessive physical strain such as physical work or overindulgence in sex, emotional stress such as terror, sorrow, anger and anxiety, or improper diet, The practitioner must carefully diagnose the root causes and determine the course of treatment.