Stomach Yin deficiency wèi yīn xū · 胃阴虚

Stomach yin deficiency is the pattern name for the picture in which the moistening, cooling aspect attributed to the stomach is described as depleted, leaving a stomach that is dry and slightly hot.

The recorded features are: a dull burning discomfort in the upper abdomen; hunger without any desire to eat, or eating only a little; a dry mouth and throat, worse at night; retching or hiccups; dry, constipated stools; a red tongue with little fluid, sometimes with cracks, and with a reduced or absent coating - in advanced descriptions, a mirror-smooth tongue; and a fine, rapid pulse. The classical texts attribute it to a febrile illness that has consumed fluids, to prolonged illness, to a diet of hot and spicy food, and to the overuse of drying or warming medicinals.

The conditions that produce a similar list include atrophic gastritis - including the autoimmune form that leads to pernicious anaemia - reflux, functional dyspepsia, Sjogren's syndrome, and the dry mouth produced by anticholinergic and antihistamine medicines. A smooth, denuded tongue is not specific to this pattern either: iron deficiency, folate deficiency, B12 deficiency and oral candidiasis all produce one.

The features that call for investigation rather than description are: progressive difficulty swallowing; vomit that contains blood or looks like coffee grounds; black stools; unintended weight loss; anaemia; and the first appearance of indigestion after the age of fifty. Sudden severe upper abdominal pain with a rigid, board-like abdomen is treated as a perforation and is an emergency. The association between atrophic gastritis and gastric cancer risk is real, but who gets screened and how is decided by local guidelines and by what endoscopy shows, not by a pattern name.