The many pathways of water – a guide to Wu Ling San and the Ling-Gui formulas

The combination of the 2 herbs fu ling and gui zhi appears in several formulas in the Shanghan Lun and in the Jingui Yaolue. This combination functions to stimulate fluid circulation and urination in case of fluid retention.

Gui zhi is an important herb of the Tai Yang conformation, with the action of stimulating movement in the body, including circulation of qi and blood as well as fluids.

According to the Shen Nong Ben Cao Jing:

“Gui zhi is acrid and sweet in flavor and warm of qi, it warms the channels and frees the flow of the vessels.”1

The combination Gui zhi with fu ling directs its stimulatory function towards focusing on fluid regulation.

The clinical importance of the formulas containing this combination stems from the importance of fluid regulation to our bodily functions. Water comprises an average of 60-70% of the adult body. The water contents of tissue changes from organ to organ, with some organs such as the liver comprising over 80% water.

It is therefore not surprising that modern research has concluded that “The regulation of body fluid balance is a key concern in health and disease”2.

The basis of water balance in the body is regulation of water intake and water output, which is achieved through complex body mechanisms creating thirst to induce water intake, absorption and metabolism of fluids, as well as mechanisms controlling urine concentration levels. Therefore symptoms of thirst sensation, drinking habits and urine amount and color are valuable sources of information to assess the fluid situation in the body.

Dehydration will usually manifest with symptoms of thirst (with or without the ability to drink) and scanty concentrated urine. The Shanghan Lun differentiates between dehydration due to lack of water consumption and dehydration due to obstruction of fluid absorption and movement. Clinically the symptoms are often similar, however the treatment is very different, which ensues the need for differential diagnosis.

This clinical differentiation is introduced in line 71 of the Shanghan Lun, which also introduces the formula Wu Ling San.

Wu Ling San

Line 71:

太阳病,发汗后,大汗出,胃中干,烦躁不得眠,欲得饮 水者,少少与饮之,令胃气和则愈。若脉浮,小便不利,微热消渴者,五苓散主之。

When in greater yang disease, after sweating is promoted and great sweat issues, (if there is) dryness in the stomach, vexation and agitation with insomnia, and a desire to drink water, giving a small amount of water will harmonize the stomach so that recovery (will ensue).
If the pulse is floating and (there is) inhibited urination, slight heat, and dispersion thirst, wu ling san governs.3

This clause begins with a description of fluid loss through sweating, which has led to dehydration, identified by thirst and general discomfort. The solution in this case is supplementing fluid by drinking. There is an emphasis on drinking slowly and gradually in order to allow proper restoration of water balance.

In Line 59 there is another description of dehydration, this time mentioning diarrhea as another cause for fluid loss, and using urine as a diagnostic factor:


When after great precipitation, sweating is then promoted, and (as a result) urination is inhibited, this is because liquid and humor have collapsed. Do not treat (this), once the urine is disinhibited, the person will spontaneously recover.3

Combining these two clauses we can summarize dehydration as a loss of fluid caused by outward sweating or downward excretions, leading to a need to supplement water by drinking; today infusion can be used to supplement fluids in more extreme cases of dehydration. Monitoring symptoms of thirst, discomfort and urine flow (concentration and amount) gives us information regarding the state of water balance in the body. If after consuming water there is an improvement in the symptoms then it is not necessary to give any additional treatment.

The second part of line 71 introduces us to the formula Wu Ling San for the treatment of situations where there is a problem with fluid circulation causing fluid accumulation in some areas together with dryness in others. Although symptoms including thirst and scanty urine might be misleading at first, the proper treatment strategy in this case is not supplementation of water, but rather stimulating urination.

We are often taught that signs of dryness in the body indicate damage of Yin. However it is repeatedly indicated in the Shanghan Lun that this could also be indicative of damage to Yang, as in this case where the problem is not the amount of fluids, but the ability to transport them.

Differential diagnosis in this case can be done by observing the symptom dynamics of the thirst and urine: in a normal situation thirst leads to drinking and water is absorbed through the system into the blood circulation and into the tissues. In the event that there is damage to the circulation of fluids, this could be due to improper absorption in the digestive tract. This will lead to “flooding” of the digestive tract and symptoms of discomfort following drinking, a sense of fullness in the stomach, and in more severe cases vomiting of fluids and/or watery diarrhea. In this situation the fluids of the bodily tissues are not replenished and there can therefore be symptoms of thirst, general discomfort and scanty urine that are indicative of dehydration. In order to restore the proper fluid circulation, it is first necessary to drain the accumulated fluid and repair the absorption mechanisms of fluid.

The following symptoms, which are mentioned in relation to the formula Wu Ling San, demonstrate the obstruction of the digestive system:

  • Vomiting of fluid is mentioned in line 74
  • Sensation of fullness in the epigastric ( xin xia pi 心下痞) is mentioned in line 156. The clinical presentation of this particular form of xin xia pi will be accompanied by thirst and scanty urine, as well as a sensation of fluids in the stomach following fluid consumption.
  • A clinical presentation of vomiting and diarrhea together with thirst is described in line 386 as an indication for Wu Ling San. In this line there is a differential diagnosis between the formulas Wu Ling San and Li Zhong Wan. Both treat fluid accumulation in the digestive system which manifests in symptoms of thirst together with discomfort in the stomach, tendency for diarrhea, nausea and vomiting. Li Zhong Wan is used when the underlying cause of these symptoms is yang deficiency, and there will therefore be additional signs of cold and weakness.
  • Discomfort in the abdominal area following drinking, with a sense of urgency to urinate resulting in a scant amount of urine, is described in line 127.

These symptoms all demonstrate that if the yang does not function properly to absorb and circulate the fluids, then just adding more fluids to the body will not result in relief of symptoms. It is important to remember that also in the classic case of dehydration, drinking a large amount of water can cause vomiting, and therefore fluids must be supplemented slowly and gradually as stated in line 71.

The Shanghan Lun focuses on the digestive tract in correlation to fluid accumulation, however, there are many underlying causes for fluid retention in varying degrees of severity. The list includes hormonal imbalance, metabolic disorders, inflammatory disorders, lymphatic insufficiency, injury and trauma to tissue, cardiac, liver or kidney diseases and mechanical obstructions such as tumors. Wu Ling San can relieve the water accumulation and improve water circulation and drainage, both by improving movement in the lymphatic system as well as drainage from the bladder. However, this formula cannot address all the underlying causes, and modifications will be required accordingly.

The symptom of edema itself is not mentioned in the lines discussing Wu Ling San, but presence of edema is a commonly accepted symptom associated with the use of this formula.

Ingredients of Wu Ling San

The ingredients of the formula are well tailored to repair the water circulation mechanisms:

Ze Xie 19g

Zhu Ling 12g

Bai Zhu 12g

Fu Ling 12g

Gui Zhi 7.5g

The warm and acrid stimulatory effect of gui zhi promotes fluid circulation.

Fu ling with its bland and neutral qualities, acts as both a diuretic as well as a spleen strengthener.

The combination of these two herbs is therefore very efficient in stimulating the movement and the drainage of the fluids.

The drainage and diuretic properties of this formula are enhanced by the function of the herbs zhu ling and ze xie.

The combination of fu ling with bai zhu addresses the digestive and metabolic mechanisms involved.

Ling-Gui Formulas

The lines discussing Wu Ling San illustrate a situation where disorder in fluid circulation manifests in signs of dryness. Clinically dryness does not necessarily develop. The source text has therefore supplied us with additional formulas addressing the different manifestations of fluid imbalance: the group of formulas known as “Ling-Gui”. This is a group of 3 formulas, all of which are composed of 3 identical herbs + 1 herb specific to each formula. The identical herbs are:

Gui Zhi

Fu Ling

Zhi Gan Cao

The addition of zhi gan cao to the fu ling+gui zhi combination creates several additional actions. The combination gui zhi+zhi gan cao is an important synergistic pair in the Shanghan Lun for supporting the Heart Yang. In correlation to fluid management, the heart is the pump that activates the circulation. Zhi gan cao also enhances fu ling’s action on supporting the function of the spleen. The spleen is linked both to the metabolic function, as well as to the regulation of muscle tissues, supporting the repair of fluid management.

The 3 formulas are:

1. Fu Ling Gan Cao Tang

Fu Ling 6g

Gui Zhi 6g

Zhi Gan Cao 3g

Sheng Jiang 9g

This formula treats fluid accumulation without signs of dryness. This formula is introduced in line 73 of the text, where it is specifically stated that the difference between this formula and wu ling san is the absence of thirst.

In line 356 a clinical manifestation of palpitations in the epigastrium and cold extremities are an indication of fluid retention which should be treated with fu ling gan cao tang.

Clinically this formula is used to treat edema when there are no symptoms suggestive of dryness, or when the therapeutic focus is on benefiting the circulation within muscular tissue. The fourth ingredient of the formula – sheng jiang – is an indicative herb for harmonizing the stomach. It is used in the Shanghan Lun for muscular related disorders when its dosage is larger relative to the other formula ingredients.

2. Ling Gui Zao Gan Tang

Fu Ling 40g

Gui Zhi 20g

Da Zao 5 pieces

Zhi Gan Cao 10g

This formula is introduced in line 65 of the text. A symptom mentioned in the source text is a sensation of palpitations felt in the area of the lower abdomen. According to some physicians this is a direct result of obstruction in the fluid circulation.

Another symptom is that the patient is inclined to develop running piglet (ben tun), which is a sensation of gushing upwards from the lower abdomen towards the chest, often associated with anxiety attacks. This formula is not appropriate for treating ben tun itself, but can be used to prevent its outburst. This is achieved by the calming and harmonizing effect of da zao which is added to the 3 standard herbs which regulate fluid circulation.

This formula has a weaker activity of invigoration and drainage compared to the two formulas mentioned above. It is however very useful in the clinic and in my opinion warrants further exploration. I identify it’s mild stimulatory and regulatory effect on fluid circulation together with its sedative effect on a manifestation of gushing upward from the lower abdomen to the chest, to be correlated to regulating movement of the Chong meridian.

3. Ling Gui Zhu Gan Tang

Fu Ling 20g

Gui Zhi 15g

Bai Zhu 10g

Zhi Gan Cao 10g

This formula is mentioned in line 67 of the text. The clinical manifestations described in relation to this formula are:

  • A sensation of fullness and counter-flow in the epigastrium
  • A sensation of surging upward into the chest
  • Dizziness when standing
  • A deep and tight pulse

The text does not state clearly the cause of obstruction and disruption to the flow of qi. This is often the case in the Shanghan Lun, and the cause is deduced from the recommended formula. In this case, since a ling-gui formula is recommended, it is commonly understood that fluid accumulation is at the root of these symptoms.

This formula is often used for fluid accumulation which does not necessarily cause edema, but does cause disruption to various functions in the upper part of the body. Examples include: chronic inflammation of the upper respiratory tract or the upper digestive tract causing increased production of exudate; fluid in the ear causing dizziness, vertigo or tinnitus.

In this formula bai zhu is used, creating the combination fu ling+bai zhu which is useful for strengthening the metabolic function. In addition this combination helps to regulate the flow of qi in the body:

  • Bai zhu supports the upward movement of qi from the middle burner to the upper burner, thus promoting the metabolic process connecting the qi of the spleen with the qi of the lungs and enhancing the immune system.
  • Fu ling supports the downward movement allowing for removal of excess by-products of the metabolic process.

It is also mentioned that a situation indicative of Ling Gui Zhu Gan Tang can develop into involuntary motions of shaking and jittering. However, in the event these symptoms (which could be associated with neurological disorders) have developed, this formula is no longer appropriate. The text does not recommend which formula should be used, but the formula Zhen Wu Tang can be considered in these cases.

The 4 formulas described in this article are extremely useful and of a wide therapeutic range. I would like to conclude with a reminder that differential diagnosis is always necessary. These formulas all support the moving quality of yang qi, and are therefore warm in nature. If there are signs of heat, they are either in need of modification or not appropriate for the situation.


  1. English translation from: Yang Shouzhong. The Divine’s Farmer Materia Medica – A Translation of the Shen Nong Ben Cao Jing. Blue Poppy Press. Boulder Co. 1998.
  2. Roumelioti, ME., et al. “Fluid balance concepts in medicine: Principles and practice”. World Journal of Nephrology. 2018; 7(1): 1–28.
  3. English translations taken from: Feng Ye, Nigel Wiseman, Craig Mitchell. Shang Han Lun: On Cold Damage, Translation & Commentaries. Paradigm Publications. Brookline, Massachusetts. 1999.

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