The formula zhi zi chi tang is a small formula that treats a broad spectrum of conditions. It is indicated for “formless heat” which is lodged in the chest, constricting the movement of blood and qi in the upper burner.

Indications

Conditions it can treat can be categorized into three main groups:

1. Inflammatory Diseases

Inflammatory diseases that affect the upper burner area, including lungs, heart, and upper digestive tract. Symptoms can include fever, sensation of burning in the chest area, chest constriction or pain, difficulty in breathing, bad smell coming from the mouth, throat or nose. The heat can cause damage to tissue possibly resulting in symptoms of bleeding from inflicted area. Laboratory tests can also be used to confirm the presence of an inflammation.

From the perspective of the six classifications of disease, this condition is linked to excess heat in the yang ming.  The manifestation of this condition in relation to zhi zi chi tang is discussed in lines 221 and 228 of the Shanghan Lun.

2. Cardiac Diseases

Cardiac diseases resulting from the heat that damages the circulation of qi and blood in the chest. That could be linked to inflammatory processes in the heart and within the blood vessels. Symptoms include discomfort in the chest, upper back, neck or left shoulder (manifesting as pain/tightness/pressure), shortness of breath, discomfort in epigastric region.

From the perspective of the six classifications of disease this condition is considered a result of a complication of a prior condition (often due to inappropriate treatment) that has transmuted into a condition which cannot be diagnosed or treated directly by any one of the six bodily systems. In the Shanghan Lun, these conditions are referred to as huai bing 坏病 (lit. bad diseases). The manifestation of this condition in relation to zhi zi chi tang is discussed in lines 77 and 78 of the text.

3. Mental Agitation

Mental agitation resulting from the heat upsetting the shen. This can be manifested in symptoms of irritability, anxiety, insomnia, and palpitations.

Diagnosis

In order to apply this formula correctly it is important to discern the condition is caused by formless heat. Diagnosis can be obtained by attention to the following principles of differential diagnostics:

Excess heat vs. Deficient heat

Both types of heat are manifested in symptoms such as aversion to heat, sweating, redness (face, lips, tongue, etc.) foul odors and burning sensations. The formula zhi zi chi tang is appropriate only to disease caused by excess heat. Signs indicative of excess include a thick and yellow tongue coating, a large or forceful pulse, and aversion only to heat.

It should be noted that symptoms we have learned to associate with deficient heat, such as heat and sweating in the “five palms” or heat and sweating only in the head region, are specifically mentioned in the Shanghan Lun as symptoms of constricted excess heat.

Formless Heat vs. Heat with Form

Heat that has developed form is heat that can be expelled from the body be removing its substance. Examples include constipation, fluid retention, cysts, nodules and tumors. Formless heat can be diagnosed as heat that cannot be removed from the body by removing a certain substance or mass.

An additional diagnostic factor the text provides is distinguished by palpation of the body. According to this, hardness is indicative of form, and softness indicates lack of form. Modern diagnostic tests can also be informative to the presence of masses, however we still need to assess their correlation to the clinical manifestations and dynamics of disease.

Stagnation Caused by Heat

The clinical manifestation indicative of zhi zi chi tang includes signs of qi and blood stagnation. In order to understand the quality and characteristics of this stagnation, we need to understand how heat creates stagnation.

The word stagnation itself, is often cause of confusion. Stagnation implies obstruction of motion. However the concept of stagnation is much broader, it also refers to unregulated motion. Healthy circulation in the body is generated from yang qi, which connects the internal bodily functions with the rhythmic circulation of external cosmic forces. Pathological heat can influence this motion causing the body to beat to the rhythm of a different drum. When this heat is the generating force of movement, the resulting motion becomes harmful and incites symptoms indicating stagnation such as discomfort and pain. These symptoms are similar to symptoms resulting from liver stagnation or cold.

In order to differentiate the nature of stagnation, it is first necessary to determine whether there is heat or cold involved in the clinical manifestation. This is why the text emphasizes that the use of this formula is appropriate when there is aversion to heat without any aversion to cold. Additional symptoms of heat affecting the body could include tendency to constantly move with difficulty in staying still, and associative thoughts with difficulty in calming the mind and impulsive actions.

Mechanism of Action

The formula zhi zi chi tang clears excess heat lodged in the chest and restores regulation to the movement of qi and blood. It is composed of two herbs with complementing qualities:

Zhi Zi

9 gr, cold and bitter, clears heat from all three burners, including the chest and heart. It induces downward motion in order to clear heat through the urine. It treats both physical and emotional symptoms caused by excess heat.

Dan Dou Chi

6-9 gr, acrid and sweet, disperses and encourages upward and outward motion. Focuses the action of the formula on the upper burner.

This combination is sufficient to restore movement, there is no need to add herbs that invigorate the movement of qi or blood.

Modifications

Zhi zi gan cao chi tang – Excess heat damaging the qi

In Su Wen chapter 5 it says:

壮火散气，少火生气
A strong fire disperses qi. A small fire generates qi.

Translation by Paul U. Unschuld and Hermann Tessenow

The small fire is yang qi which reinforces and restores. The strong fire is pathogenic heat which damages and destroys. Symptoms of damage will manifest alongside the above-mentioned symptoms of heat, and can include shallow breathing, lethargy and difficulty in speaking.

The modification is composed of the original two ingredients with the addition of zhi gan cao. The mild and harmonizing effect of zhi gan cao is an advantage in this case, since strong tonifying herbs might increase the pathological heat. Together with the original two herbs of the formula, heat can be cleared, proper motion restored and healing processes can ensue.

Zhi zi sheng jiang chi tang – Symptoms of vomiting

This modification is the addition of sheng jiang to the original formula. In choosing sheng jiang to treat symptoms of stomach upset, rather than a herb that clears heat in the stomach, we can deduce that there is no additional need to address the heat, but rather a need to enhance restoration of proper movement. Sheng jiang is warm and acrid, it cannot treat the fire itself, but gently harmonizes the stomach qi to restore balance.

It is also noteworthy that in all versions of the formula there is mention of possible vomiting after taking the formula. If this occurs the formula should be discontinued. It is not clear from the text if the formulas are meant to cause vomiting or if this is an indication of improper treatment. The simple answer is to determine according to the situation following the vomiting. If there is an improvement in the symptoms then this was part of the healing process, if there is no improvement or even worsening of the symptoms, than the formula was not appropriate for the condition and diagnosis should be reassessed. Personally, I have often prescribed this formula for my patients and never encountered vomiting as a side-effect. However many have complained that dan dou chi has an awful taste.

Zhi shi zhi zi chi tang – Excess heat causing constriction in the middle burner

This formula treats excess heat that is constricting both the upper burner as well as the movement of qi in the middle burner. In addition to the symptoms indicative of the original formula, such as irritability, discomfort or pain in the chest, insomnia, and anxiety, there are also symptoms of abdominal discomfort, bloating and fullness. The heat has not developed form so there should be no symptoms of constipation or hardness in the abdomen.

The modification includes the addition of zhi shi that invigorates movement of qi in the middle burner. In addition, the dose of dan dou chi is increased to overcome the added challenge of improper qi circulation in two burners of the body. In the event the heat does take form in the shape of constipation or hardness, da huang can be added to the formula.

This modification appears in the Shanghan Lun in line 393 which belongs to the section discussing recovery following a debilitating disease. This is an indication that the focus of the formula is on guiding the rehabilitation of bodily functions rather than focusing on combating the disease in its acute phase. An interesting detail regarding this modification is the instruction to take it with “clear starch water”. This is made by steeping grains in water for a few days until there is an odor and a sour taste. In modern understanding this seems to describe the use of probiotics to enhance the body’s healing processes.

Contraindications for using zhi zi chi tang formulas

These formulas are essentially cold and dispersing. If the patient’s constitution is one of spleen deficiency this formula could cause further damage. Therefore, in cases when there are signs of excess heat in the upper or middle burner together with signs of spleen weakness, the text suggest adding gan jiang to address both components of the disease.

This is an example of an important feature that is presented throughout the Shanghan Lun: hot and cold ingredients do not balance each other’s temperature. They are combined when it is necessary to address complicated conditions that involve both pathological heat and pathological cold. This perspective is essential to working with herbs. A hot herb will remain hot even in a cold-natured formula and a cold herb will remain cold even in a hot-natured formula.