Source 出处 · Jingui Yaolüe · Doses are not given here: they are set by a licensed practitioner for the individual.
Safety. Da Jian Zhong Tang is the most severe of the middle-warming formulas, and the source text is unusually vivid about what it is for: great cold pain in the chest and abdomen, vomiting that prevents eating, and - in the phrase that has made the passage famous - pain running up and down that cannot be touched. Four ingredients: shu jiao is acrid and hot and drives the cold; gan jiang warms the middle and holds it; ren shen supplements what has been depleted; jiao yi, malt sugar syrup, is sweet and slow-acting and is there for the pain. Building a pain remedy around a sugar is the part that surprises modern readers, and the classical reading is straightforward - the sweetness is doing the easing. This entry describes that and does not defend it.
The phrase that cannot be touched is where this entry has to stop describing and start cautioning, because what the classical text records as the signature of the pattern is, in modern terms, the signature of the emergency. Tenderness that makes a patient refuse to be examined - guarding, rigidity, rebound - is peritoneal irritation, and peritoneal irritation means perforation, ischaemia, or an inflammatory process that surgeons need to see. The acute abdomen list behind severe abdominal pain runs through appendicitis, cholecystitis and biliary colic, perforated peptic ulcer, intestinal obstruction, diverticulitis, pancreatitis, ruptured or dissecting aortic aneurysm, ectopic pregnancy, testicular torsion, mesenteric ischaemia - the one whose pain is out of proportion to the examination and which should be thought of first in atrial fibrillation - inferior-wall myocardial infarction, which presents as upper abdominal pain, and ketoacidosis. The standing modern rule for undifferentiated acute abdominal pain is not to purge, not to apply heat, and not to cover it with analgesia before someone has seen it. Nothing in this entry is an exception to that rule.
Three specific cautions follow. Shu jiao is Zanthoxylum - Sichuan pepper - and it is not the same plant as black pepper; the tingling compound hydroxy-alpha sanshool is what gives it its character, and a concentrated decoction is not the same exposure as a seasoning. Gan jiang is dried ginger, hotter and less dispersing than the fresh root, and not interchangeable with it. Jiao yi is malt sugar, made by sprouting grain; the grain used varies with the maker, and for anyone who must avoid gluten that is a question to ask rather than an assumption to make. It is also, plainly, a sugar load - and this matters more here than in most formulas, because the syrup is a principal component rather than a trace. Ren shen is immunologically active and has documented case reports of interaction with warfarin, with the direction and size of the effect unsettled.
大建中汤是温里诸方中最峻烈的一首，原文对它所主的情形写得异常生动：心胸中大寒痛，呕不能饮食，以及最著名的那一句 —— 上下痛而不可触近。四味药：蜀椒辛热以逐寒，干姜温中而守，人参补其已虚，胶饴甘缓以止痛。把一味糖放进一首止痛方里，是现代读者最意外的地方，而古典解释很直白：甘能缓。本条目描述这一点，不为它辩护。
「不可触近」这四个字，正是本条目必须停止描述、开始提示的地方 —— 因为古典文献把它当作此证的指征，而在今天的语言里，它恰恰是急症的指征。拒按、肌紧张、反跳痛，是腹膜刺激征；而腹膜刺激征意味着穿孔、缺血，或外科需要亲眼看到的炎症过程。剧烈腹痛背后的急腹症清单贯穿急性阑尾炎、胆囊炎与胆绞痛、消化性溃疡穿孔、肠梗阻、憩室炎、胰腺炎、腹主动脉瘤破裂或夹层、异位妊娠、睾丸扭转、肠系膜缺血（其痛与体征不成比例，房颤患者应首先想到），以及表现为上腹痛的下壁心肌梗死与酮症酸中毒。对未判明病因的急性腹痛，现代通行原则是：不攻下、不热敷、不在有人看过之前用镇痛把它盖住。本条目所述没有任何一条构成该原则的例外。
三处具体注意：蜀椒是花椒属（Zanthoxylum），不是胡椒；产生麻感的羟基-α-山椒素是它的特征成分，而浓煎的汤液与作料级别的暴露不是一回事。干姜是干燥姜根，性更热而较不发散，与生姜不可互代。胶饴是麦芽糖，由谷物发芽制成 —— 所用谷物随制法而变，对必须避免麸质的人而言，这是应当去问的问题，不是可以默认的前提；同时它明明白白是一份糖负荷，而这一点在大建中汤里比其他方更要紧，因为胶饴在此是主药之一而非点缀。人参具免疫活性，与华法林相互作用的病例报告有文献记载，作用方向与大小尚未定论。