Combining Similar Formulas and Herbs Reduces Toxic Side Effects and Enhances Efficacy

Can TCM prescriptions be written like solving a math problem, grouping similar formulas and herbs together like combining like terms? The answer is yes.

From ancient times to the present, many great clinical TCM physicians have done exactly this; they simply call it by different names. Liu Dazhou called it "joining past and present," while Jiao Shude called it "combined formulas" (hefang). If we read the case records of clinical physicians, we find abundant examples in their prescriptions of combining several famous formulas of similar or complementary effect into a single prescription. Some classic famous formulas in history were themselves formed by combining smaller classic formulas.

The greatest benefit of combining category-formulas and category-herbs is lowering toxic side effects while enhancing efficacy. The simplest example: traditional TCM holds that both Wugong (Scolopendra, centipede) and Quanxie (Scorpio, scorpion) relieve spasms, so Zhijing San (Spasm-Relieving Powder) combines them in equal amounts. Professor Zhang Tingmo mentions that studies show 0.5 g of centipede combined with 0.5 g of scorpion produces a stronger antispasmodic effect than 5 g of centipede alone or 5 g of scorpion alone, while 5 g of centipede or scorpion alone is more toxic than 0.5 g centipede plus 0.5 g scorpion. Such combination therefore both reduces toxicity and raises efficacy.

Can we extend this from combining category-herbs to combining category-formulas? Again, yes. For example, Chaihu Guizhi Tang and Jingfang Baidu San have very similar effects. Combining one portion of Chaihu Guizhi Tang with one portion of Jingfang Baidu San produces a more marked effect than using 5-10 portions of either alone, while the side effects are far smaller.

I have practical experience in this. During the COVID-19 outbreak, I combined Chaihu Guizhi Tang with Jingfang Baidu San, Ping Wei Wan and Xie Bai San to create the Chai Gu Jiedu Tang and Chai Gu Jiedu Wan formulas (several of my earlier articles introduced this composition in detail), and their efficacy was truly immediate. I used them to treat many ordinary COVID patients and also to rescue several severe COVID cases, with satisfactory clinical results.

Of course, the Chai Gu Jiedu Wan and Tang I created are a little more complex than the simple idea of combining category-formulas and category-herbs described above, but they are only one step further on that basis.

The main indications of Chaihu Guizhi Tang and Jingfang Baidu San are body pain, aversion to cold and nausea, but COVID-19 symptoms are more complex; COVID patients also have loss of smell and taste, anorexia, abdominal distension, skin allergy, cough and pleural effusion. When composing the formula, I therefore decomposed COVID's indications into those of Chaihu Guizhi Tang/Jingfang Baidu San, those of Ping Wei Wan, those of Xie Bai San, and so on, and then combined the corresponding classic formulas, which gave good efficacy against COVID. I used this as a universal formula throughout the pandemic, treating all kinds of COVID and post-COVID patients, and most reported good results.

This is a slightly more complex approach to combining category-formulas and category-herbs, but it is really just the skill that comes with rich clinical experience. One of my students entered Beijing University of Chinese Medicine last year; after enrolling she came to see me once and asked what the core of studying TCM is. I told her the core of TCM is formula-pattern and herb-pattern—this is not my original idea; I first saw it in the writings of Professor Hu Xishu, who said that formula-pattern is the apex of pattern differentiation and treatment.

The vitality of TCM lies in efficacy; what guarantees TCM efficacy? I think the least controversial basic principle in the TCM community is pattern differentiation and treatment (bianzheng lunzhi). What is its core? Its core is formula-pattern or herb-pattern. What is a formula-pattern or herb-pattern? Simply put, it is the indication of a formula or herb—the problem this formula or herb can solve.

These problems can be concretely translated into the patient's various symptoms and signs. For example, the indication of Guizhi Tang is "spontaneous sweating, aversion to cold, generalized fever, floating moderate pulse"; a striking indication of Gegen Tang is "stiff and tight neck and back" (discomfort and stiffness of the shoulders and back); the indication of Su Lian Yin is vomiting with diarrhea. If we remember many formula-patterns and herb-patterns, we can quickly find the corresponding formula in clinical practice. Treating with the corresponding formula rapidly relieves symptoms, and the patient gains confidence in the physician.

Memorizing formula-patterns and herb-patterns is far harder than learning the whole yin-yang and five-phases system. A bright child with a good teacher can learn that jargon-like system in one to seven days; if he is also eloquent, he can go out and discourse impressively. But after learning it this way, can he treat disease? I guarantee he knows basically nothing about treating disease.

To become a TCM physician of outstanding clinical efficacy, one must work hard to learn the indications of formulas and herbs, and constantly review that knowledge; even if one cannot recite it all, one must build reflex-like memory. When a patient describes his symptoms and suffering, and we observe his external signs, our minds must immediately bring to mind one or more formulas matching those symptoms and signs. With this foundation, our clinical ability can at least reach a competent level.

Going a step further, we must be able to analyze the patient's condition, break down his symptoms, and combine similar formulas. I neither reject the small classical-formula approach nor cease exploring the large-combination approach; I have benefited greatly from both. Simple diseases respond immediately to classic small formulas, while complex, refractory diseases can have their suffering reduced by large combination formulas.

A reasonable large combination formula is never a mere pile of herbs; it is built by combining, according to certain rules, several formulas proven by many people to have a particular effect, into one orderly large prescription. Such a large prescription uses small herb doses but achieves outstanding efficacy.

When I use Chai Gu Jiedu Wan for COVID or wind-cold or gastrointestinal colds, the total pill dose per administration is only a few grams, and any single herb within it is measured in hundredths of a gram; yet often a single dose brings down a fever or resolves the illness. There is no need to routinely use Chaihu in dozens or hundreds of grams; this dosing is far safer, the efficacy is higher, and the treatment cost is lower. What is wrong with such an approach?

Studying formulas and Chinese herbs has become my daily compulsory course for over a decade. My emphasis in learning TCM is on formulas and herbs, while reading case records to see how other physicians prescribe and understand their composing logic. This is a very pragmatic method of study; in my familiar fields I now genuinely have reflex-like memory. Often, while a patient is still describing symptoms, the corresponding symptom-relieving formula has already appeared in my mind; I combine several formulas I can think of into one prescription that solves part or all of the patient's problems.

Of course, some patients have reached the point where their oil is exhausted and their lamp is dying—the terminal stage of an incurable disease; experienced clinicians recognize such patients quickly. At that point we should avoid using drugs to worsen or prolong suffering, and should comfort the family.

We must hold an attitude of reverence toward the classic famous formulas created by renowned physicians through the ages, and must not disdain them. The reason they became famous and have not faded with time is that their formulas were repeatedly verified effective in clinical practice. Medicine is an empirical science; formulas validated by countless people have established efficacy, and we should respect them, learn from them humbly, remember them, and verify them in practice.

Some people are self-important, looking down on the world, or complacent and sectarian, scorning formulas created by other physicians; such small-minded, arrogant people are not suited to medicine. To study medicine one must draw on the strengths of all to succor the people, never treat other people's lives lightly, and always prioritize treatment plans verified by predecessors as effective and safe. This spirit matches the evidence-based medicine advocated in modern Western medicine.

Lay a solid foundation and memorize a certain number (I personally suggest at least 2,000) of formula and herb indications relevant to one's specialty, so that clinical prescribing is never shot without aim. When composing formulas and dosing, one's thinking must be clear and logical. Combining category-formulas and category-herbs is one such clear, logical approach. The more we apply it in practice and listen to patients' feedback after dosing, the more difficult problems we can solve, and the more solidly our confidence in our work grows.

I do not like to speak of the vague term "insight"; I believe good medical thinking can be popularized and understood by most people, like Bai Juyi's poetry. A person of ordinary ability who is willing to study medicine, willing to endure hardship, and who masters good learning and formula-composition methods can also become a physician of decent clinical efficacy. If one day I stand at a lectern to teach students, I will certainly promote my simple, practicable, easy-to-learn and quickly actionable approach to formula composition, rather than mystical theories.