Written by Lauren Lines, Dipl. O.M. (NCCAOM)® on July 24, 2023

Formula Spotlight: Liu Yi San

Liu Yi San formula image

Beware, summer warriors! The sun’s fury not only brings the scorching heat but also the dreaded summer stomach flu. For our readers living in high humidity climates, the oppressive combination of heat and dampness can cause additional unpleasant symptoms. As temperatures and humidity levels soar, so does the risk of falling prey to diarrhea, nausea, fever, dysuria, thirst, and vomiting. Fortunately, Chinese herbal medicine has a highly targeted approach to resolving these symptoms and not letting them dampen your summer fun. We can understand this methodology further by taking a closer look at the simple, yet powerful, formula Liu Yi San (Six-to-One Powder).

Usage

As the heat ascends and gives rise to symptoms like fever and irritability, dampness grinds the fluid dynamics of the San Jiao to a sticky halt. Liu Wan-Su, author of the Liu Yi San formula, strategized that the best method for resolving this particular kind of summer heat invasion was to focus on smoothing out the movement of fluids and qi throughout the San Jiao. The chief ingredient Hua Shi (Talcum) not only clears the summer heat, but it also resolves the dampness that weighs us down with symptoms like nausea, vomiting, and diarrhea. Deputy Gan Cao (Licorice Root) helps to generate fluids (important to balance Hua Shi’s diuretic effect!), mildly resolves toxicity, and harmonizes the Middle Jiao. This formula’s source text recommends the use of Zhi Gan Cao (Licorice Root processed with honey) which has a more tonifying effect on the Middle Jiao and moistening effect on the Lungs over Gan Cao.

Herb images Herb images

It is important to understand that Liu Yi San more commonly acts as a foundation for larger, more specifically targeted formulas. On its own, it can be effective for very mild summer heat invasions with damp accumulation. Original preparation is to grind six parts Hua Shi to one part Gan Cao into a powder and take with warm water, or add the same powder ratio to a cheesecloth bag and take as a decoction. The powder can also be applied topically to rashes caused by damp heat.

Exams

Studiers of the CALE can take a break. Liu Yi San isn’t currently on the list of tested formulas. NCCAOM preppers need to pay closer attention, though. Fortunately, with only two ingredients, it isn’t a difficult formula to memorize. Studying modifications of this formula will likely be the best use of time. With respect to the textbook tongue and pulse presentation, a thin, yellow, and greasy tongue coat with a soggy, rapid pulse are what you might expect with heat and damp. Liu Yi San is contraindicated for patients who do not have damp symptoms and cautioned in cases of deficiency. Take note that the Chens’ Chinese Herbal Formulas and Applications lists pregnancy as a contraindication while Bensky’s Chinese Herbal Medicine: Formulas & Strategies does not.

Herb enthusiasts, stay cool and keep studying and/or practicing! If the heat and humidity does happen to get the better of you or someone you know this summer, don’t forget about the simple, yet effective, principles of Liu Yi San.