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Syndrome differentiation according to defense(wei), vital energy(qi), nutrient(ying), blood(xue)
Ye Tianshi(1667-1746AD)

This method was first put forward by Ye Tianshi (1667-1746AD), a Qing Dynasty physician, in his book Wenrelun (On Febrile Illnesses). He classified the clinical manifestations of acute febrile diseases(wenbing) caused by exogenous pathogens into four stages: defense(wei), vital energy(qi), nutrient (ying) and blood(xue). These are the four body strata used to explain the location and severity of pathological changes, and form the basis of clinical treatment. This method not only characterizes the four types of febrile disease syndromes, but it is also a reflection of the four grades of severity of febrile diseases during their development.

The defense(wei) stage refers to disorders in the outer defensive forces of the body - protective qi. It usually occurs at the onset of an epidemic febrile disease, the pathological changes are present in the lungs, skin and hair.

The vital energy(qi) stage
refers to disorders in the body's inner defensive forces, which manifests as an interior heat syndrome caused by excessive heat evils. In this case, both the body's disease preventing forces and pathogens are very strong, resulting in intense struggling.

The nutrient(ying) stage
occurs when pathogenic heat is transmitted into the qi of the blood. Ying is a component of the blood, so the disease is actually located in the heart and pericardium.

The blood(xue) stage
represents further invasion of the ying system by the evils. It results in excessive heat stirring the blood and further disturbing the mind. The pathological changes are mainly in the liver and kidneys.

Syndromes according to the stages of defense(wei), vital energy(qi), nutrient(ying) and blood(xue)
Stage Syndrome Main features
Wei Febrile pathogens invading body surface Fever, slight aversion to wind and cold, very little or no sweating, cough, runny nose, headache, sore throat, slightly thirsty and body aches. On examination, the tongue tip and margin are red and covered with a thin white or little yellow coating, and the pulse is floating and rapid.
Qi Heat retention in lung Fever, sweating, thirst, cough with yellow sticky sputum, asthma, chest pain, chest fullness and sore throat. On examination there is a red tongue with yellow coating, and a rapid pulse.
Excess heat in qi system High fever, irritability, extreme thirst with preference for cold drinks, profuse sweating, flushed face and coarse breathing. On examination there is a dry and yellow tongue coating and surging pulse.
Heat retention in stomach and intestine Thirst with preference for cold drinks, anxiety, delirium, fever in afternoon, constipation or diarrhea and distention and pain in abdomen, which feels better when pressed. On examination, there is a dry and yellow tongue coating, and a deep and forceful pulse.
Damp-heat retention in spleen Slight fever, thirst but without desire to drink, chest fullness, nausea, heavy sensation in body and limbs, sleepiness, perspiration with sticky sweat, diarrhea and yellow and scanty urine. On examination, the tongue is red with a yellow thick and greasy coating and the pulse is hesitant and rapid.
Ying Heat damaging nutrient yin Fever (worse at night), chest fullness, insomnia, or even coma and delirium and transient rashes. On examination, there is a deep red tongue and thready and rapid pulse.
Heat attacking pericardium High fever, irritability or apathy, stupor, delirium, tongue stiffness and cold limbs. On examination there is a deep red tongue and rolling and rapid pulse.
Xue Blood heat lead to circulation disorder High fever, irritability, insomnia, mania, transient rashes, feverish sensation of the palms and soles, and bleeding disorders. On examination, the tongue is dry, deep red or purple color and the pulse is rapid.
Liver heat stir up winds High fever, headache, dizziness, stupor or irritability, upward turning of eyes, tightly closed jaw, a stiffly back and neck and agitation or convulsions. On examination, the tongue is deep red and the pulse is taut and rapid.



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Written By:
Raka Dewan, Integrated Chinese Medicine Holdings Ltd.

Angela Collingwood MSN, Integrated Chinese Medicine Holdings Ltd.
Raka Dewan, Integrated Chinese Medicine Holdings Ltd.

Rose Tse, Integrated Chinese Medicine Holdings Ltd.