Yin Vacuity & Damp Heat

by Bob Flaws

Last Friday, I posted a blog based on an article in issue #2, 2009 of Si Chuan Zhong Yi (Sichuan Chinese Medicine). Well here’s another one. It from an article appearing on pages 50-51 of the same issue. The original article is by Long Yong-ting from the Clinical Research College of the Chengdu University of Chinese Medicine & Pharmacology. Basically, the article is about the connection between yin vacuity and damp heat and why these two patterns often appear simultaneously. Certainly, this is my own clinical experience, and Dr. Long does a nice job with her explanation. So here’s a brief summary of that article.

Follow up:

Dr. Long begins by first mentioning that there are two types of damp heat –internally engendered and externally contracted damp heat. She then goes on to talk about yin vacuity and internal dampness. According to the Nei Jing (Inner Classic), “Root of Spirit)”: “Yin vacuity leads to no qi.” However, in this saying, “no qi” does not really mean no qi; it means scanty or less qi or, in other words, qi vacuity. If yin fluids are sufficient, they are able to transform qi. Therefore, if fluids are vacuous, this leads to “scanty qi” or qi vacuity. Vice versa, qi is able to move fluids. Hence, if the qi is scanty, this may lead to disturbances in the movement of fluids. In other words, qi vacuity lacking the power to move and transform fluids may give rise to internally engendered dampness. This, in turn, may cause even more serious yin vacuity. If fluids are sufficient, the blood has a source from which it can be engendered. This is because blood and fluids share a common source. Then, since blood and essence share a common source, blood vacuity may lead to yin vacuity.

Next Dr. Long describes the relationship between damp heat and yin vacuity causing internal heat. If, for any reason, the body becomes yin vacuous, yin fails to control yang and yang becomes hyperactive, thus giving rise to internally engendered heat. This heat may consume and burn fluids and humors, cooking the fluids into phlegm. This engenderment of phlegm may then block the transformation and engenderment of fluids and blood. Thus the yin vacuity may become even worse. If this internally engendered heat combines with the internally engendered dampness, this will give rise to damp heat. Hence there is a close relationship between yin vacuity and damp heat which, in fact, is bi-directional or “mutually engendering.”

From here, Dr. Long discusses yin vacuity and external contraction of the six environmental excesses. According to Dr. Long, habitual bodily yin vacuity may lead to damp evils taking advantage of this vacuity to enter the body, remembering that, if there is a yin vacuity, there is also an element of qi vacuity. As it is said, “If the righteous exists internally, evils cannot attack.” If these damp evils depress the yang qi, this may give rise to depressive heat, and this depressive heat may mutually join with the dampness to become damp heat. This transformation of dampness into damp heat is all the more likely if yang is hyperactive, as it tends to be when yin is vacuous and insufficient. Further, because external dampness and heat have a mutual affinity and predilection to combine, it is also possible for externally damp heat evils to enter the body when it is yin vacuous. So there can be damp heat and yin vacuity due to either 1) the sole contraction of external dampness or 2) the contraction of damp heat already combined. Nevertheless, whether the condition started off as simply dampness or combined dampness and heat, once there is damp heat and yin vacuity, the damp heat will make the yin vacuity even worse.

While it might seem contradictory to have both yin vacuity (a species of dryness) with damp heat (a species of dampness) at the same time, as Dr. Long shows, there are a number of different disease mechanisms explaining why these two patterns commonly present simultaneously and why, in fact, these two patterns are mutually engendering. Because beginner’s textbooks only discuss patterns one by one in their simple, discrete forms, many students and younger practitioners may not realize these facts. Therefore, it is very important to know that yin vacuity-damp heat is a commonly seen real-life combination pattern.

As for what to do about this, one the one hand, one needs to enrich yin and engender fluids, while, on the other, one needs to clear heat and eliminate dampness. However, because yin-enriching medicinals may engender excessive dampness and dampness-eliminating medicinals may further damage yin, one needs to be careful in how one achieves these two basic principles in tandem. As an example of the skillful achievement of these two principles at the same time, Dr. Long presents a formula from the Tai Ping Hui Min He Ji Ju Fang (formulary of the Pharmacy Service for Benefitting the People in the Tai Ping [Era]) called Gan Lu Yin (Sweet Dew Beverage) which happens to be one of my favorite, lesser know formulas. This formula consists of:

Shu Di Huang (cooked Radix Rehmanniae)
Sheng Di Huang (uncooked Radix Rehmanniae)
Mai Men Dong (Tuber Ophiopogonis)
Tian Men Dong (Tuber Asparagi)
Shi Hu (Herba Dendrobii)
Huang Qin (Radix Scutellariae)
Yin Chn Hao (Herba Artemisiae Scopariae)
Zhi Qiao (Fructus Aurantii)
Pi Ba Ye (Folium Eriobotryae)
Gan Cao (Radix Glycyrrhizae)

Within this formula, the two Di’s, the two Dongs, and Shi Hu all enrich yin and engender fluids. In addition, Sheng Di Huang and Mai Men Dong do also clear some heat. Huang Qin, Yin Chen Hao, and Pi Ba Ye clear heat and eliminate dampness while not damaging yin. Zhi Qiao transforms dampness and rectifies the qi, thus preventing the slimy, enriching, and potentially stagnating yin-supplements from aggravating the dampness. Gan Cao harmonizes then all the other ingredients in the formula. Of course, as Dr. Long notes, one should make various additions and subtractions based on the exigencies of the individual case. She also discusses several other formulas that she likes to use for this complicated pattern depending on the viscera involved.

No matter how one skins this cat (i.e., what formula one uses), because of the mutually engendering nature of yin vacuity and damp heat, when these two disease mechanisms occur together, they also must be treated together. When these two occur together, you cannot treat one without treating the other. This is because these two mechanisms are “bound” or “knotted” together. This goes back to their being mutually engendering. While doing this takes a bit of skill and flexibility, it is something that is and must be routinely done in clinical practice. So I’m grateful for Dr. Long broaching this subject in her article. Hopefully, you, the reader, will find this precis helpful as well.

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