The formula Si Ni San is a popular and widely used formula for treating pathologies of liver qi stagnation and liver invading the spleen. The list of possible clinical manifestations is long and varied, including:

• Digestive problems with abdominal distention and pain, irregular bowel movements.
• Gynecological problems with irregular periods, emotional and physical symptoms of PMS and unexplained infertility.
• Problems that are diagnosed as related to stress including moodiness, aches and pains, feeling of congestion in the chest, palpitations, etc.

However, the potential and accurate application of this formula can be understood much more if studied through the Shanghan Lun, where it is first mentioned. This formula is mentioned in the Shanghan Lun in one line only. This is surprising considering the wide range of clinical application and the justified popularity of this formula. What is even more surprising is the fact that this formula is mentioned in the chapter dedicated to pathologies of the Shao Yin, a conformation which is usually associated with the terminal stage of illness and is commonly linked to pathologies of Heart and Kidney, with no direct relation to the pathologies of Liver.

While it might be tempting to assume that this line was misplaced, and should belong to another conformation, such as Jue Yin, the text itself states clearly that this is no mistake, beginning the line with the words: “ When in a Shao Yin Disease…..”

Line 318:

少阴病，四逆，其人或咳，或悸，或小便不利，或腹中痛，或泄利下重者，四逆散主之。

When in Shao yin disease (there is) counterflow cold of the limbs, the person may cough or have palpitations, or inhibited urination, or pain in the abdomen, or diarrhea with rectal heaviness, Si Ni San governs.

– English translation taken from: Shang Han Lun: On Cold Damage, Translation & Commentaries. Feng Ye, Nigel Wiseman, Craig Mitchell –

The Shao Yin conformation is responsible for the delicate and fragile processes essential to the existence of the body. These processes are linked to the potential stored within the Jing and to the mind-body connection. It is therefore easy to understand why a deficiency in this conformation manifests in defeat of body and mind, and a physical and emotional surrender to the disease. But this is not the case discussed in line 318. This line is unusual in the chapter of the Shao Yin, as it does not present a situation of diminishing life force, there is no mention of the characteristic symptoms of a Shao Yin pathology such as a minute pulse or watery stools with undigested food or a desire only to sleep.

This line is rather a presentation of a very different pathology of the Shao Yin, one which is not terminal or progressive, but can still have a significant effect on quality of life.

The fragile internal processes, which are governed by the Shao Yin, need to be protected from external influences. The Yang of this conformation therefore functions in the depth of the subconscious realm, hidden from the conscious experience and the intellect. However, while protected from the external world, the Shao Yin must not be disconnected from it since it is an integral part of the body as a whole, and an essential contributor to every process in the body. It must be able to communicate with the other conformations in order to maintain a state of well-being. When this conformation is over-protected and blocked from the inside, it will not endanger the survival but it will create a sense of detachment from the internal core, affecting the quality of a variety of bodily functions.

The list of symptoms detailed in line 318 is a clear reflection of the wide scope of potential symptoms an obstruction of Shao Yin might manifest. This list begins with the symptom which the formula is named after: si ni 四逆, commonly translated as frigid extremities. This symptom represents the dynamics of the underlying pathology.

Literally this phrase means “4 rebellions” referring to the 4 limbs and to the inability of Yang qi to fulfill its function in nourishing and warming the external and superficial layers of the body, in this case due to an internal obstruction. The list continues with other functions that could be affected by this obstruction and includes:

• Cough: obstruction and counter-flow affecting the respiratory function. This could also include wheezing and chest discomfort. Acute respiratory infection must be ruled out before diagnosing the Si Ni San syndrome as the cause of these symptoms.
• Palpitations: obstruction of internal yang qi affecting regular rhythmic motion.
• Inhibited urination: flow of fluid as well as ability of the bladder to empty is dependent on free flow of qi, this could manifest as weak urinary flow, incontinence, and difficulty in emptying of bladder. Acute urinary tract/kidney/prostate infections must be ruled out before diagnosing the Si Ni San syndrome as a cause of these symptoms.
• Pain in the abdomen: obstruction of flow could affect the regulation of muscles causing muscular pain of abdominal muscles as well as muscles of the internal organs. This could also be manifested in other skeletal muscles throughout the body.
• Diarrhea with rectal heaviness: obstruction of internal yang qi affecting regular rhythmic motion, in this case of the peristalsis. This symptom could also be a manifestation of the obstruction causing problems to metabolic and digestive processes.

This list is far from complete, it is just an example of the diversity and wide scope of clinical manifestation of this syndrome. Differential diagnosis cannot therefore rely on the symptoms themselves, but rather on the dynamics of the pathology:

Despite symptoms of functional deficiencies, there is no real deficiency of qi or yang but rather inability to utilize their strength due to obstruction. It can be characterized by stress as a trigger and accompanied by an emotional sense of frustration, being misunderstood or lack of fulfillment. These patients often have decreased physical well-being without pathological findings which could explain their condition.

Ingredients:

The formula is composed of 4 herbs with equal dosage.

Chai Hu

Shao Yao (Bai Shao or Chi Shao)

Zhi Shi

Zhi Gan Cao

As characteristic of the Shanghan Lun, full understanding of the formula lies in the understanding of the combinations:

Chai Hu + Shao Yao:

Chai Hu is acrid and cool, encourages movement from the internal to the external and superficial levels.

Shao Yao is bitter and cold, encourages movement into the muscles and blood vessels.

Together these herbs have a regulating effect on motion which is often attributed to the Liver organ, motion of dispersion and storing, allowing for cleansing and rejuvenating.

Chai Hu + Zhi Shi:

Chai hu is acrid, encouraging an upward and outward motion.

Zhi Shi is bitter, encouraging a downward motion.

Together these herbs have regulating effect on the motion which is often attributed to the Stomach and the Spleen which govern digestion and metabolism.

Shao Yao + Zhi Gan Cao:

Shao Yao regulates blood. In this formula the herb usually used is Bai Shao which is also sour and has a tonifying effect on the blood and nutritive qi (ying qi).

Zhi Gan Cao is sweet, tonifies and harmonizes the body.

Together these herbs soften muscles, both skeletal and organ, enabling improved blood flow to areas of tension, thereby improved their function.

With only 4 ingredients this formula accomplishes a harmonizing influence through a combination of acrid, sour, bitter and sweet; and a regulating influence through a combination of upward, downward, inward and outward movements. This does not create a neutral formula, but rather a clever strategy to induce movement and renew communication between the fragile life forces from deep within the Shao Yin and the dynamic forces activating daily processes on the surface. This is the reason why this formula is so clinically popular and diverse: it creates an improved internal environment for awakening the body’s integral healing wisdom.