2. Wei-Qi-Ying-Xue Differentiation

2. Wei-Qi-Ying-Xue Differentiation

This system divides exogenous febrile diseases into four stages according to their progression: Wei-level, Qi-level, Ying-level, and Xue-level syndromes.

(1) Wei-level Syndrome

Headache, fever with chills (more heat than cold), thirst and dry throat, cough, floating and rapid pulse. Treatment includes Sangju Yin (from "Wenbing Tiaobian") and Yinqiao San (from "Wenbing Tiaobian").

(2) Qi-level Syndrome

High fever and intense thirst, profuse sweating, abdominal distension and pain, severe constipation, red tongue with dry yellow coating, and a large, bounding pulse. Treatment includes Baihu Tang (from "Shanghan Lun") and Chengqi Tang (from "Shanghan Lun"), among others.

(3) Ying-level Syndrome

Alternating fever and intense thirst, restlessness and delirium, red tongue with little coating, and a fine, rapid pulse. Treatment includes Qingying Tang (from "Wenbing Tiaobian") with added ingredients.

(4) Xue-level Syndrome

Alternating fever and intense thirst, confusion and delirium, convulsions and palpitations, rash, various bleeding manifestations, dark red tongue with no coating, and a fine, rapid pulse. Treatment includes Huaban Tang and Angong Niuhuang Wan (from "Wenbing Tiaobian").

This differentiation was proposed by the warm-disease scholar Ye Tianshi, who built upon the theories of Ying, Wei, Qi, and Xue in the "Inner Canon" while also drawing inspiration from Zhang Zhongjing's Six Meridians Differentiation, combined with his own extensive clinical experience. The Wei-level syndrome essentially corresponds to the Taiyang disease in the Six Meridians Differentiation, but focuses more on pathogenic heat invading the exterior; the Qi-level syndrome is largely equivalent to the Yangming syndrome in the Six Meridians, yet through elaboration on pathogenic factors lingering in the Triple Burner, it incorporates heat-related syndromes affecting the chest, lungs, liver, and kidneys, thus better reflecting clinical realities than the Yangming syndrome alone; the Ying-level syndrome represents a deeper exploration and development of the Qi-level syndrome, characterized primarily by severe heat damaging yin; the Xue-level syndrome further develops the Ying-level syndrome, marked by even more severe clinical manifestations, including heat severely injuring yin while simultaneously entering the pericardium, causing blood to flow erratically, and triggering wind due to excessive heat.