In eleven years of teaching Chinese herbal medicine, I have observed that students and practitioners often have difficulty in mastering prescriptions, and matching them correctly to a pattern diagnosis. This has led to reliance on a handful of treatment manuals or proprietary product literature. This literature largely lists conditions under biomedical disease name headings, with few Chinese medical patterns, limiting potential choices and reducing clinical effectiveness. The application of herbal medicine is subsequently reduced to symptomatic application to disease.

Chinese herbal medicine is largely based on a core ‘family’ of prescriptions that have been modified over time to treat an increasingly complex array of disease patterns. If one simply tries to memorize this large group of prescriptions individually, the amount of data becomes overwhelming very quickly, leading to confusion. Earlier generations found this task difficult as well, and prescription manuals with thousands of formulas to match common diseases were not uncommon by the Tang dynasty. In modern TCM colleges in the West, much of the emphasis seems to be on learning and memorizing up to three hundred prescriptions. These are often taught without any contextual or historical basis. One prescription is linked to other prescriptions mainly because they fall into the same therapeutic category (such as supplementing yin, or clearing heat from the viscera). Although there is a relationship of therapeutic similarity within categories, that which makes each prescription distinct is easily blurred by these generalized similarities. The distinctions can only be made by understanding the underlying philosophy of each physician who designed the prescription, in a historical context.

Qin Bo-wei, the famous twentieth century Chinese physician and one of the “architects” of modern TCM, distilled the essence of this method as an equation:
disease factor + location of the disorder +
symptoms = pattern = prescription

One determines the ingredients of the prescription from the disease pattern. Each ingredient treats an aspect of the pattern, and interacts with the pattern according to classical Chinese medical philosophy and a long history of clinical application.

The basis of this approach to medicine was developed in the Shang Han Lun/Treatise on Cold Damage, the Han dynasty text that is still regarded as the seminal medical treatise that originated the method of bian zheng lun zhi, determining treatment by pattern identification. According to this method, one chooses medicinal prescriptions according to specific disease patterns, including the factors of time, location of the disease, and change of symptoms. When studying the Shang Han Lun, the student discovers a unifying principle embedded in the text. As Craig Mitchell and Feng Ye state in their introduction to their Shang Han Lun translation, “each (disease) pattern can be treated by a variety of methods, using medicinal drugs that are combined on the basis of their therapeutic effects into a limited number of formulae whose constituents can be varied to address different presentations.”

1. These relationships can be described as algorithms: repetitive patterns or sequences of events or numbers that repeat themselves automatically in the natural world. The entire text from beginning to end is a continuum, unified as it traces the progression of disease through the three yang and three yin channel/stages. The symptoms transform over time and progression towards the body interior, changing in quality, forming new patterns, leading to resulting modifications in their associated prescriptions. From the initial channel disease, tai (greater) yang disease, to the terminal channel disease, jue (reverting) yin disease, one can relate any pattern or prescription to another pattern or prescription. A high percentage of prescriptions can be seen to be modifications of gui zhi tang/Cinnamon Twig Decoction, primarily used to treat tai yang bing/greater yang disease. The remaining prescriptions are in families, such as the cheng qi/qi coordinating prescriptions that are based on da huang/rhubarb root for treating yang ming bowel diseases, or the si ni tang/Counterflow Cold Decoction family of fu zi/rx. Aconite prescriptions that treat tai (greater) yin and shao (lesser) yin diseases.

Later authors developed new schools of thought that were related to the Shang Han Lun approach, including Li Dong-yuan’s school of fortifying spleen and stomach, Zhu Dan-xi’s school of supplementing yin, and the warm disease prescriptions of Ye Tian-shi and Wu Ju-tong. Zhu Dan-xi developed a method of classifying prescriptions according to four basic categories of blood, qi, depression and phlegm. He chose a limited number of basic prescriptions, and modified them to treat a wide variety of diseases. This approach is still valid today. For example, si wu tang/Four Substance Decoction is the basis of dozens of gynecological prescriptions, and can be modified from its basic ingredients (bai shao/rx. peony, di huang/rx. rehmannia, dang gui/rx. angelica sinensis, and chuan xiong/rx. Ligusticum wallichi) by adding and subtracting ingredients, modifying dosage, and using different preparation methods.

In order to illustrate further, let us examine an example of a prescription from Zhang Jing–yue (style name Jie-bin), the author of the Jing yue quan shu (17th century). The prescription we choose is ji chuan jian/Benefit the River Flow Decoction, used for chronic constipation caused by kidney yang vacuity. The symptoms are constipation with clear copious urination, lower back pain and chill in the lower back. The pulse is deep and thready, tongue pale. The ingredients are rou cong rong/hb. Cistanches, dang gui/rx. Angelica sinensis, niu xi/rx. Achyranthes, ze xie/rz. Alisma, zhe ke/fr. Citri aurantium (bitter orange), and sheng ma/rz. Cimicifuga. If one examines the medical philosophy of Dr. Zhang (who was nicknamed “Rehmannia Zhang”, as he developed many prescriptions to supplement the kidneys), we see that he primarily uses the method of kidney yang supplementation to treat constipation. For this he uses rou cong rong which is warm, supplements kidney yang, but is also very moistening. To supplement the blood and moisten the intestine, he uses dang gui. However, the additional medicinals reveal the subtleties of his treatment method. Niu xi descends the blood to the lower burner, helping to enrich the blood and warm the yang. Ze xie is used to guide the other medicinals to the kidney, and drains turbid yin within supplementation of kidney yang. Zhe ke is the only medicinal used to actually deal directly with constipation, as it descends the qi and breaks up the accumulated stool. However, Dr. Zhang has also added sheng ma to raise the clear yang and restore the normal qi transformation, aiding normal digestion and evacuation. Combined with zhi ke, sheng ma restores the normal flow of qi upwards and downwards. We can conclude that the therapeutic goal of this prescription is to supplement kidney yang and blood, moisten the intestines, raise the clear yang, descend turbid yin, and mildly break up accumulated stool.

Another group of prescriptions which are closely related to each other, and therefore demonstrate how herbal algorithms evolve, are based on jin gui shen qi wan/Golden Cabinet Kidney Qi Pill. Jin gui shen qi wan is the original di huang/rx. Rehmannia prescription from Jin gui yao lue/Prescriptions from the Golden Cabinet by Zhang Zhong Jing, a companion text to the Shang Han Lun focused on internal disorders. It contains, and is designed to treat kidney yang vacuity disorders. Many years later, Qian Yi, a twelfth century pediatrician, removed fu zi/rx. Aconite and rou gui/rx. Cinnamon from the prescription, because he wanted to avoid harsh hot ingredients that he felt were too strong for children. In the process, he originated the premier prescription to supplement kidney yin, Liu wei di huang wan/Six Flavor Rehmannia Pill. Zhang Jing-yue removed the draining ingredients (ze xie/rz. alisma and mu dan pi/rx. Moutan, and added gan cao/rx. glycyrrhiza and gou qi zi/fr. lycii to make the prescription even stronger in supplementing kidney yin. This prescription is zuo gui yin/Restore the Left Cool Decoction. Other physicians such as Zhu Dan-xi further modified the Six Flavor Rehmannia Pill to produce such prescriptions as Da bu yin wan/Great Yin Supplementing Pill, which strongly supplements kidney yin with shu di huang/rx. Rehmannia and gui ban/plastrum testudinis (deep-fried fresh water turtle shell), and clears fire with jiu shao zhi mu/rx. Anemerrhena (wine-fried) and chao huang bai/cx. Phellodendron (dry-fried).

In conclusion, to master a formulary of Chinese herbal prescriptions, one first has to learn the medical philosophy of the Shang Han Lun and other great physicians such as Zhu Dan-xi, Li Dong-yuan, Gong Ding-xian and Ye Tian-shi. One must have a grasp of pattern differentiation, pulse and tongue diagnosis, and understand the pathomechanisms that underly disease.

For the last 10 years, Z’ev Rosenberg has served as Chair of the Department of Herbology at Pacific College of Oriental Medicine (San Diego). He has been in private practice since 1983 and is a consultant and product developer for K’an Herb Company. He writes for several professional Oriental medical journals, and is working on a book on immunology and Chinese medicine. In 1999, he was elected as a Fellow of the National Academy of Acupuncture and Oriental Medicine, an organization of scholars and senior practitioner/teachers in the profession.

1 Mitchell, Craig, Ye, Feng, and Wiseman, Nigel, Shang Han Lun/On Cold Damage, Paradigm Press, Brookline, Ma. 2000, pg. 2.