The Six Pathogenic Factors

In Chinese medicine, the six pathogenic factors are understood to be the six environmental pathogenic factors that can invade the body and cause disease. They can invade the body singularly or in various combinations. They are classified in TCM as:

  • Wind
  • Cold
  • Summer-heat
  • Dampness
  • Dryness
  • Heat (Fire)

In TCM literature, they are sometimes referred to as the Six Pernicious Influences (Liu-Yin) or Six Evils. They are considered to be meteorological or climatic factors which play a part in disease. Each of the above pathogenic factors can be of exterior or interior origin, however, they are generally considered to relate mainly to outside influences. They generally correspond to a full pattern according to the Eight Principles. The invasion of the body by a pathogenic factor usually arises as a result of an imbalance of Yin-Yang.

Some internally generated pathogenic factors also give rise to similar pathological signs and symtoms as the exterior climatic factors.