Jade Dew Powder for Infant Summer Vomiting and Diarrhoea

Three substances and nothing else: gypsum and calcite in equal weight with a quarter as much raw licorice, ground fine and stirred into water that may be warm or cool as the child will take it. It is the lightest thing in the section and close to being a drink rather than a medicine, which is also what the chapter asks of it — the section head gives it twice, once for the hot-milk injury after the purge and again for the summer-month vomiting with body heat, and pairs it with 益元散 for the child who sleeps without showing the white of the eye. This is the first of the ten formulas in 吐瀉 and the place to say plainly what the illness is. Vomiting and diarrhoea in a small child is acute gastroenteritis: rotavirus above all before vaccination, then norovirus, then the bacterial causes — Shigella, Salmonella, Campylobacter, the toxigenic strains of E. coli — and, in the tropics, cholera. It was and in places still is a leading killer of children under five, and the thing that kills is not the infection but **dehydration**. A child's fluid reserve is small, the losses are fast, and death follows hypovolaemia within a day or two. The intervention that reverses it is **oral rehydration solution**: salt, sugar and clean water in fixed proportion, a few cents a sachet, taken by mouth in small repeated sips. It works because glucose drags sodium and water across the intestinal wall even while the gut is inflamed and secreting, and that piece of physiology was not known until the middle of the twentieth century. Nothing in the Donguibogam, or in any medical text before then, contains it. Alongside it: rotavirus vaccination now prevents a large share of these episodes outright; zinc supplementation shortens an episode and reduces the next one; and **antidiarrhoeal drugs are contraindicated in young children** — loperamide can cause ileus and has killed infants, and the old opiate and atropine mixtures were worse. **None of the ten formulas in this section, this one included, replaces fluid.** A child vomiting and purging needs rehydration first and everything else second. Given that, this leaf is among the least harmful answers in the section. It puts nothing poisonous into the child, and the vehicle is a cup of water, which is the right direction even if the water carries no sodium and no glucose in rehydrating proportion. Gypsum and calcite are the standard pair for stomach heat with thirst and they do nothing for the fluid loss; the honest reading is that the formula treats the thirst and leaves the cause of the thirst untouched. — Eui Young (Justin) Chung, L.Ac., Dipl. O.M.