Cold and Heat of the Eight Principles

Cold and heat are two principles for differentiating the nature of disease.
Cold syndromes are pathological changes and symptoms caused by exogenous pathogenic cold or constitutional yang deficiency. Clinical manifestations of cold syndromes are: aversion to cold and preference for warmth ;tastelessness in the mouth;absence of thirst;pallor;cold extremities;clear and profuse urine;loose stool;pale tongue proper with a white slippery coating;slow pulse, etc.These are all signs of excessive yin.
 
Heat syndromes are caused by exogenous pathogenic heat or constitution yin deficiency. The symptoms of heat syndromes incluse:fever;preference for cold;thirst with preference for cold drinks;flushed cheeks and redness of the eyes;yellowish and scanty urine;constipation;red tongue proper with a dry yellowish coating;rapid pulse,etc.These are signs of preponderant yang.