San Huang Shu Ai Tang for Unabating Diarrhea and Dysentery
"San Huang Shu Ai Tang" comes from the Lei Zheng Huoren Shu. Its composition is: Huanglian (Coptis, Rhizoma Coptidis), Huangqin (Scutellaria, Radix Scutellariae), and Huangbai (Phellodendron, Cortex Phellodendri), each 7 qian 5 fen (22.5 g), and Shu Aiye (processed Mugwort Leaf, Folium Artemisiae Argyi) 5 qian (15 g). Coarsely crush the above into pieces the size of hemp or beans; add 500 ml of water, decoct down to 350 ml, strain, and take warm twice daily. Nowadays one can simply buy the decoction pieces of Huanglian, Huangqin, Huangbai, and Aiye from a pharmacy and decoct and take them in the same way.
This formula clears heat, resolves dampness, and stops dysentery; it treats damp-heat dysentery. It is very similar to Huanglian Jiedu Tang (Coptis Detoxifying Decoction, composed of Huanglian, Huangqin, Huangbai, and Zhizi — four herbs). The two differ by only one herb yet have quite similar effects; Huanglian Jiedu Tang also drains heat and stops dysentery and can treat damp-heat dysentery.
However, all four herbs in Huanglian Jiedu Tang are bitter-cold, so patients with a preexisting stomach-cold pattern who take it after contracting dysentery may develop the side effect of stomach pain. In that case, replacing the Zhizi in the formula with the warm Mugwort Leaf avoids the side effect of Huanglian Jiedu Tang; hence the indications of this formula differ slightly from those of Huanglian Jiedu Tang.
Chinese herbs stop diarrhea very quickly. For acute diarrhea treated with Huanglian Jiedu Tang or San Huang Shu Ai Tang, if one dose does not work, it is almost always because the wrong formula was used, and it should not be taken again. When using such formulas, one should also follow the principle of "stop once the disease is resolved"; once diarrhea has stopped, the medicine should not be continued, for further use may cause constipation.
In the author's experience, this formula can be used not only for damp-heat dysentery but also for acute diarrhea caused by food poisoning, and for cancer patients with acute diarrhea and tenesmus after chemotherapy. However, diarrhea caused by intestinal tumors responds poorly to such formulas; such patients should be treated with antitumor formulas.