Chai Hu is a commonly used herb, associated with febrile diseases as well as with mental and physical manifestations of liver qi stagnation. Its classical description and uses reveal insights into its broad scope of its actions, offering guidance for the proper ways to use it.

According to the Shen Nong Bencao Jing:

Chai Hu is bitter, balanced and non-toxic.
Treats the heart and abdomen; gets rid of bound qi in the intestines and stomach, of accumulations and gatherings of food and drink, and of evil qi of cold and heat; and pushes out the old to usher in the new. Consumed over a long time, it lightens the body, brightens the eyes and boosts essence.

Translated by Sabine Wilms

Chai Hu appears in seven formulas of the Shanghan Lun, in all of them it is the chief herb. Six of them are related to shao yang disorders, and one is associated with the shao yin conformation. Both these conformations are characterized as “shao” translated as “small”. This can be interpreted as referring to the fragile dynamics of these two conformations that can be easily disrupted.

Chai hu for resolving shao yang disorders

The shao yang conformation functions like a pivot that regulates between the requirements of the internal environment and the reality of the external environment. These two environments both influence the body’s ability to function. Often in life these two environments don’t align. It is the dynamics of the shao yang that enables us to navigate the differences.

However, the tension and disharmony between these two environments can occasionally lead to obstruction of the shao yang. In acute febrile disease, obstruction of the shao yang is characterized by the symptom of alternating fever and chills. In chronic miscellaneous conditions this can manifest physically as recurrent sensations of discomfort or pain, often in pivot areas of the body associated with the shao yang such as the side of the head and neck, the rib cage, the area of the diaphragm and the waist. Additional clinical manifestations associated with shao yang distress include digestive dysfunction, often in form of nausea and epigastric discomfort.

Emotional difficulty is closely linked to pathologies of this conformation. Shao yang emotional symptoms manifest as lack of vitality and joy, weakened sense of excitement and interest, tendency towards apathy or pessimism.

In order to resolve problems of the shao yang, the Shanghan Lun instructs us to use the formula xiao chai hu tang in different variations and modifications. This formula is incredibly versatile and can be adapted to a wide variety of clinical manifestations and complications. In all the different applications chai hu is always present as the chief herb, with a dose 2.5 times larger than the rest of the herbs in the formula. It is important to maintain this higher dose in order to ensure the effect on the shao yang.

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For instructive details on the use of xiao chai hu tang see:
The layers of Xiao Chai Hu Tang >>

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Chai hu for resolving shao yin disorders

The shao yin conformation secures the delicate materials and functions that are at the core of our existence. It contains the primal jing that connects our body and mind to create a unified system. In order to ensure it is protected from irreparable damage it needs to be protected deep within the hidden realms of our body.

Experiences of fear, particularly existential fear or basic lack of security can lead this conformation to close off from the inside. This is completely different from the shao yin disorder that is a condition of severe deficiency of the body essence associated with degenerative diseases. Obstruction of the shao yin is not linked to deterioration of the body, but it will create a sense of detachment from the internal core, affecting the quality of a variety of bodily functions, both physical as well as emotional.

Symptoms are widespread, including aches and pains, digestive disorders, sleep disorders, gynecological disorders, often without a clear diagnosis, identifying it as psychosomatic. Emotionally, feelings of frustration, being misunderstood or lack of fulfillment are often described by patients with obstruction of shao yin. When unresolved, these feelings often lead them down a path to despair.

In order to resolve obstruction of the shao yin, the Shanghan Lun instructs us to use the formula si ni san with different variations. Similar to xiao chai hu tang, this formula is also incredibly versatile and can be adapted to a wide variety of clinical manifestations and complications, all of which rely on the action of chai hu.

It is however important to note the difference in relative dose compared to xiao chai hu tang. In the case of si ni san, in order to enable the formula to affect the shao yin, the dose of chai hu should be equal to the dose of the other herbs in the formula.

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For instructive details on the use of si ni san see:
The Character of Stagnation in the Shanghan Lun – Si Ni San >>

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Life challenges us, that’s just the way it is. Our innate bodily wisdom in form of these two conformations provides us with tools to cope with the obstacles we encounter. But sometimes it’s just too overwhelming and our system shuts down. Chai hu can help reactivate and open the possibilities of healing within, or in the words of the Shen Nong Bencao Jing, chai hu “may make the body light, brighten the eyes and boost the essence”.