Inter-rejection of yin and yang, a special pathogenesis in imbalance between yin and yang, includes two aspects, predomination of yin rejecting yang and predomination of yang rejecting yin. The cause of such a pathological change lies in the fact that either yin or yang becomes predominant and drives the other side outside, leading to a complicated pathological condition marked by disagreement between the nature of disease and symptoms.

     

Predomination of yin rejecting yang refers to a pathological state in which predominant yin drives yang-qi outside, leading to a pathological change marked by true interior cold and false exterior heat. The nature of this syndrome is cold, but the manifestations appear febrile because yang-qi is driven outside. Take deficiency of yang generating interior cold for example. 

If it develops to a stage marked by extreme predomination of yin-cold and external floating of yang, a pathological change of predominant yin rejecting yang will be caused, the manifestations of which include cold limbs, diarrhea with undigested food and indistinct pulse due to predominance of yin-cold as well as some pseudo-febrile signs such as fever in spite of desire for quilt in the body and reddish cheeks.

      

Predomination of yang rejecting yin refers to a pathological state in which predominant yang drives yin outside, leading to a cold-like pathological change. Since pathogenic heat has deepened into the body and cannot be dispersed outside, there is pseudo-cold symptoms though the syndrome is febrile in nature. Take exuberant interior heat in febrile disease for example. Since heat is superabundant, yin and yang are in disharmony and yin-qi is blocked and rejected. The manifestations include feverish sensation in the chest, dry mouth, and dry and red tongue as well as cold limbs and aversion to cold due to the fact that extreme change of yang appears like yin.