Chaihu formulas are frequently used in contemporary clinics. One of the most frequently used formulas, Xiaoyao San 逍遙散 (Free Wanderer Powder), is a relatively recent development in the history of Chinese medicine. It first appeared, as far as I can tell, in the 11th century. However, in the intervening time and perhaps especially in the last 50 years in the US, it has become indispensible to many Chinese medicine practioners.
While I do not have a lot of experience with this formula, I do use the classical formulas from which it grows, as well as the rest of the Chaihu formulas found in the works of Zhang Zhongjing. Interestingly, there are only a handful of these formulas in those texts, and the majority are modifications of only one of these – Xiao Chaihu Tang 小柴胡湯 (Minor Bupleurum decoction).
Xiao Chaihu tang – the most famous of the classical Chaihu formulas – is a formula meant to treat Shaoyang disease.
This externally triggered illness manifests with alternating feelings of hot and cold, fullness in the chest and sides, a taciturn nature, depressed appetite, nausea or retching and often some type of thirst. However, like so many “cold damage” or “external invasion” formulas – it has application far beyond these simple, symbolic statements.
Xiao Chaihu tang and the whole family of formulas built on it are typically used, today, for many of the everyday problems people in Western nations experience. Namely, depression, anxiety, vague digestive problems, PMS, migraines and other “side of the head” headaches, appetite dysregulation and unnamable fatigue. This is, of course, in addition to the more straightforward external invasion case as described above.
In my own practice, I use Xiao Chaihu Tang as a base for anybody that manifests the pulse pattern that I learned in my lineage and at least one or two of the symptoms above.
In almost every case, this is a good first formula in a progression of treatment. It seems to resolve long standing issues, especially those of a vague, irritating nature that never quite rose to the level that the patient wanted to expressly seek out treatment for them. Often, this is a low grade depression or frequent but mild headaches not attributable to any other cause.
However, in a small number of cases, patients become seriously aggravated on Chaihu formulas.
This is particularly true, I find, when many food allergies and a leaky gut sort of picture are presenting. No matter how perfect the pulse matches the formula, no matter how many of the symptoms they have, administering Xiao Chaihu tang or any of its relatives, and even the more distant Chaihu formula Sini san just doesn’t seem to do any good.
I got to thinking about this recently, and it led me to the line for Chaihu in the Shennong ben cao jing 神農本草經 (Divine Farmer’s Materia Medica). The line in that text, as translated by Yang Shou-zhong in the Blue Poppy version of the text, says:
“Chaihu is bitter and balanced. It mainly treats bound qi in the heart, abdomen, intestines, and stomach, drink and food accumulation and gathering, cold and heat, and evil qi. It weeds out the stale to bring forth the new. Protracted taking may make the body light, brighten the eyes, and boost the essence. Its other name is Di Xun (Earth Fuming). It grows in rivers and valleys” (28).
It’s that phrase “it weeds out the stale to bring forth the new” that really gets me thinking. I’m certainly not the only one, as my single herbs teacher, formulas teacher and every other herbs teacher has sought to explain what it means.
I believe it is this phrase that can help me understand why certain patients cannot tolerate Chaihu formulas. I will return shortly to discuss this more, and to reveal the way I’m thinking about it now, but first I’d like to hear from you.
Have you ever had this type of trouble with Chaihu formulas? Have you determined why this happens? Do you have an interesting take on the “weeds out the stale to bring forth the new” phrase? Please respond in the comments!
About Eric Grey
Hi - I'm the founder of this site and the primary master of all functions here. When I'm not writing, you can find me reaching out to the Chinese Medicine community across the web and in my own backyard. I currently teach Chinese herbs at my alma mater, the National College of Natural Medicine. Additionally, I'm the founder of Watershed Wellness, a thriving local clinic in Southeast Portland in Oregon. No matter where I'm working, you'll find my focus on the Classical approach to Chinese medicine laced throughout everything I do.