Wu Mei Wan (Mume Pill) wū méi wán · 乌梅丸

Safety. The Shanghan Lun gives this in its discussion of the terminal yin stage, and it takes the trouble to separate two things that look alike. Cold reversal of the viscera is a quiet, deepening collapse. Roundworm reversal has the same cold limbs and the same faint pulse but a different signature: the patient quietens and then becomes agitated again, and then quietens, the agitation comes from worms moving up against the diaphragm, it passes, and on eating it returns with vomiting, because the worms have smelled food and come out, which is why the patient is known to bring them up. There follows one short sentence tradition has taken up and run with: it also governs enduring diarrhoea. Structurally the ten ingredients are arranged in four parties, and the classical account of why is one of the tidier pieces of reasoning anywhere in the literature. The roundworm, the line runs, is quietened by sour, made to lie down by pungent, and driven downward by bitter. So there is a sour chief in the smoked plum flesh; a pungent and hot party in asarum, dried ginger, aconite, Sichuan pepper and cinnamon twig; a bitter and cold pair in coptis and phellodendron; and behind them restorative pairs in ginseng and angelica. Whatever one makes of the mechanism, the construction is genuinely elegant and deserves to be described rather than smirked at. Then the part that has to come first. The organism is Ascaris lumbricoides, and ascendariasis is not a nuisance condition. Migrating adult worms produce biliary colic, acute cholangitis, gallstones formed around worm remnants, pancreatitis and liver abscess; and a tangled bolus of worms obstructs bowel, most often in children, with volvulus, intussusception and perforation behind it. All of that has a straight and well-evidenced modern answer. Albendazole and mebendazole are highly effective single-agent anthelmintics and the basis of both individual treatment and the school-based deworming programmes that hundreds of millions of children receive. Worms in the bile duct are removed endoscopically. Obstruction and perforation go to theatre. Against that, nothing justifies relying on a ten-ingredient pill instead, and nothing establishes this formula as an anthelmintic by modern standards. This knowledge base says so plainly rather than leaving the reader to infer it from silence. The second thing worth saying first concerns the later extension, because it is why most people meet this formula today. Enduring diarrhoea has its own long list, and it is a list rather than a diagnosis: inflammatory bowel disease, microscopic colitis, bile acid diarrhoea, coeliac disease, pancreatic insufficiency, thyroid disease, medication effects, chronic giardiasis, Clostridioides difficile, HIV-related enteropathy, colorectal cancer, and irritable bowel syndrome, which is the commonest thing on the list and the one that has to be arrived at rather than assumed. One item on it deserves naming because it kills people by surprise: Strongyloides stercoralis can persist for decades and then produce fatal hyperinfection if immunity is suppressed, which is why screening before immunosuppression is standard practice in endemic areas and in anyone with unexplained eosinophilia. There is a considerable Chinese-language literature using this formula for ulcerative colitis, diarrhoeal irritable bowel patterns and even type 2 diabetes. Those trials exist and the reviews that appraise them consistently rate the evidence low-certainty, largely on design. Existing and weak is the honest summary, and it is more useful than either repeating the claims or pretending the trials were never run. The individual materials carry their own load, and one of them twice over. Asarum belongs to the birthwort family, Aristolochiaceae, whose members contain aristolochic acid; the nephropathy and upper urinary tract urothelial carcinoma associated with that compound class come from cumulative exposure for which no safe threshold has been established, and this is why the Chinese pharmacopoeia restricts its medicinal part to root and rhizome rather than the aerial parts. Aconite is the same emergency-level poison described in Yi Yi Fu Zi Bai Jiang San and everything said there applies here with equal force. Coptis and phellodendron both supply berberine, so the berberine cautions count twice: inhibition of several drug-metabolising enzymes and transporters with raised blood levels of a long list of medicines, displacement of bilirubin in jaundiced neonates, glucose-6-phosphate dehydrogenase deficiency, and lowering of blood glucose. Both also come from bark and rhizome, so supply pressure is part of their story. Sichuan pepper is ordinary Sichuan pepper, the same thing in the kitchen jar; noting that is not reassurance, it is a reminder that this is the only ingredient you could season a dish with. Angelica contains coumarin-type constituents - sharing a word with warfarin does not make something an anticoagulant, but there are case reports of raised INR when the two are combined, and ginseng has been reported to shift INR in both directions, so anyone on warfarin is in monitoring territory rather than in dispute territory. Finally, the mume: the material used is the processed fruit, while the kernels of Prunus species are the part that holds cyanogenic glycosides - the distinction is the whole point and it is why the fruit is food and the kernel is not.