The TCM Treatment Idea of Balancing Yin and Yang, Combining Cold and Heat, and Using Both Supplementing and Purging, Seen Through the Series of Shenqi Wan Formulas

Shenqi Wan (Kidney-Qi Pill) first appears in the Jin Gui Yao Lue (Essential Prescriptions from the Golden Cabinet), hence its alternative names Jinkui Shenqi Wan or Cui's Eight-Ingredient Pill. It is a formula of excellent clinical efficacy. Later generations derived several modified formulas from it, such as Guifu Dihuang Wan, Liuwei Dihuang Wan, Zhibai Dihuang Wan, Qiju Dihuang Wan and Jisheng Shenqi Wan; these are all essentially variations built by adding and subtracting on the basis of Jinkui Shenqi Wan.

Jinkui Shenqi Wan consists of eight herbs: Shudi (Rehmannia), Shanzhuyu (Cornus Fruit), Shanyao (Chinese Yam), Fuling (Poria), Zexie (Alisma), Mudanpi (Moutan Bark), Fuzi (Aconite) and Rougui (Cinnamon Bark). The formula contains both herbs that supplement kidney yang and herbs that supplement kidney yin; it has warming-hot herbs as well as cooling herbs that clear heat; it both supplements and drains. It can be called a representative formula of balancing yin and yang, combining cold and heat, and using both supplementing and draining.

TCM holds that isolated yin cannot generate, and solitary yang cannot grow. Those who are good at supplementing yang seek yang within yin, so that yang, aided by yin, generates and transforms without end; those who are good at supplementing yin seek yin within yang, so that yin, risen by yang, has an unceasing source. If a formula contains only yang-supporting herbs, the patient, while supporting yang, often drains out yin fluids through over-warming and drying, presenting with dry mouth and tongue, irritability and restlessness. If it contains only yin-nourishing herbs without any yang-supporting herb, one easily sees problems of cloying richness obstructing the diaphragm.

Therefore, over-supplementing yin or over-supporting yang is equally unacceptable. A patient who needs yin supplementation may be given a moderate amount of yang-supporting herbs within the yin-nourishing formula to rouse the yang of spleen and kidney; a patient who needs yang support may likewise be given some yin-nourishing herbs to protect the yin of lung and kidney. Only when yin and yang are balanced will the patient take the medicine safely and steadily.

By the same reasoning, when a formula uses large amounts of warming and hot herbs, some cooling herbs should be added moderately to prevent excessive warm-drying from damaging yin and fluids; when large amounts of cold and cooling herbs are used, some warming herbs should likewise be added to prevent cold from injuring the spleen and kidney.

Supplementing formulas must also leave the pathogenic evil a way out, and pathogen-expelling formulas must also consider supporting the patient's upright qi; hence supplementing and draining must be used together. Jinkui Shenqi Wan is precisely formulated on this idea.

In the Jin Gui Yao Lue, the action of Shenqi Wan is chiefly to warm and supplement kidney yang and free the flow of urination, treating various diseases caused by kidney-yang deficiency. The text records four uses of Shenqi Wan: 1. For deficiency-tax low back pain, tension in the lower abdomen, and difficult urination, Eight-Ingredient Shenqi Wan governs. 2. For shortness of breath with slight fluid retention, which should be drained through urination, Linggui Zhugan Tang governs; Shenqi Wan also governs. 3. For wasting-thirst in men with, by contrast, excessive urination - drinking one dou of water and passing one dou of urine - Shenqi Wan governs. 4. For the "turned bladder" (bi syndrome) with inability to urinate, caused by a twisted bladder ligament: simply promoting urination cures it; Shenqi Wan is appropriate.

From these passages we can see that Jinkui Shenqi Wan is chiefly used to treat various causes of difficult or frequent urination. It suits patients with kidney-yang deficiency, sore weak lower back and legs, a persistent cold sensation in the lower half of the body, tension in the lower abdomen, difficult urination, or conversely excessive urination. In terms of pulse, the chi positions are generally deep and fine; in terms of tongue, such patients usually have a thin, white, non-dry tongue coating. Jinkui Shenqi Wan can also treat beriberi, phlegm-fluid retention, wasting-thirst (chiefly lower wasting-thirst), and the turned-bladder syndrome.

Later, the great Song paediatrician Qian Yi argued that children are a body of pure yang without yin, so their treatment principles differ from adults'; when nourishing children's kidney yin one should not simultaneously support kidney yang. He removed Fuzi and Rougui from Jinkui Shenqi Wan and adjusted the dosage of each herb, producing the well-known kidney-supplementing formula Liuwei Dihuang Wan. In terms of formulation principle, not every patient is suited to Liuwei Dihuang Wan.

Another famous Song physician, Yan Yonghe, added Niuxi (Achyranthes) and Cheqianzi (Plantago Seed) to Jinkui Shenqi Wan, producing Jisheng Shenqi Wan. Most of the Jinkui Shenqi Wan one buys in pharmacies today is actually the Jisheng Shenqi Wan formulation. With these two herbs added, the effect of Shenqi Wan in supplementing both kidney yin and kidney yang and in promoting diuresis and freeing strangury becomes even clearer. I often use Jisheng Shenqi Wan to treat pleural effusion and ascites in late-stage cancer patients, with quite obvious results.

Among the derived formulas of Jinkui Shenqi Wan is Guifu Dihuang Wan. Guifu Dihuang Wan has exactly the same herbal composition as Jinkui Shenqi Wan, differing only in the proportion of Rougui and Fuzi in the formula - yet the uses diverge greatly. Guifu Dihuang Wan has a stronger yang-supporting force, so it suits patients with severe kidney-yang deficiency. It chiefly treats kidney-yang deficiency with cold pain of the waist and knees, oedema of the limbs, difficult or excessive urination, phlegm-fluid wheezing and cough, and wasting-thirst. It is very suitable for diabetes, asthma or prostate-disease patients presenting with yang-deficiency patterns.

Later practitioners further modified Jinkui Shenqi Wan: removing Rougui and Fuzi and adding Zhimu (Anemarrhena) and Huangbai (Phellodendron) produced Zhibai Dihuang Wan, which only nourishes yin and drains turbidity and suits patients with severe kidney-yin deficiency. Removing Rougui and Fuzi and adding Gouqi (Lycium) and Yejuhua (Wild Chrysanthemum) shifts the focus to supplementing kidney and liver yin, suiting patients with liver-kidney yin deficiency presenting with dizziness, blurred vision and unclear sight.

From the art of formulating and modifying this single prescription, we can appreciate the subtlety of TCM treatment, in which "the subtlety of application lies entirely within the mind."