大黄（六两去皮） 芒硝（一升） 甘遂（一钱匕）
上三味。以水六升。先煎大黄。取二升。去滓。纳芒硝。一两沸。纳甘遂末。温服
一升。得快利。止后服。结胸兼涉阳明。仍用本汤。
大陷胸汤。由胸膈直达肠胃。亟从下夺。不用一药监制。此最猛劣之剂。故曰大。经云
。太
阳病。脉浮而动数。浮则为风。数则为热。动则为痛。数则为虚。头痛发热。微盗汗出而反
恶寒者。表未解也。医反下之。动数变迟。膈内拒痛。胃中空虚。客气动膈。短气躁烦。心
中懊 。阳气内陷。心下因硬。则为结胸。大陷胸汤主之。按动数变迟三十六字。形容结胸
之状如绘。盖动数为欲传之脉。迟则不能复传。阳邪因误下而内陷。而里饮复与之相格。心
下因硬。膈间拒痛。本方虽用硝黄。而关键全在甘遂末一味。使下陷之阳邪。上格之水邪。
俱从膈间分解。而硝黄始得成其下夺之功。若不用甘遂。便属承气法。不成陷胸汤矣。
又经云。伤寒十余日。热结在里。复往来寒热者。与大柴胡汤。若结胸无大热者。此为
水结
在胸膈也。但头微汗出者。大陷胸汤主之。观此条云。水结胸胁。而仍主此者。则全资甘遂
逐水之功也。
大黄（半斤去皮） 葶苈（半斤熬） 芒硝（半斤） 杏仁（半斤去皮尖熬黑）
上四味。捣筛二味。纳杏仁芒硝。合研如脂。和散。取如弹丸一枚。别捣甘遂末一钱匕
。白
蜜二合。水二升。煮取一升。温顿服之。一宿乃下。如不下。更服取下为效。禁如药法。
结胸者项亦强。如柔痉状。下之则和。宜大陷胸丸。按结胸而至于项强。则胸结十分紧
迫。
浊邪布满胸中。升而上阻。津液不行。筋脉失养。故如柔痉状。邪踞于上。法当峻下。但汤
剂直趋下焦。必变汤为丸。煮而连滓服之。使其逗遛病所。自上而下。方能与邪相当。而结
自解。
喻嘉言曰。方中用大黄甘遂芒硝。可谓峻矣。乃更加葶苈杏仁。以射肺邪而上行其急。
煮时又倍加白蜜令留恋而润导之。而下行其缓。必识此意。方知用法之妙。
Rhubarb Radix et Rhizoma (6 liang, peeled) Natrii Sulfas (1 sheng) Kansui Radix (1 qian bi)
The above three herbs. With water 6 sheng. First decoct Rhubarb Radix et Rhizoma. Obtain 2 sheng. Remove dregs. Add Natrii Sulfas. Boil once. Add powdered Kansui Radix. Take warm, 1 sheng at a time. If rapid purgation occurs, stop subsequent doses. Jie Xiong (Chest Binding Syndrome) involving Yangming channel still uses this Tang Decoction.
Da Xianxiong Tang (Major Trapping Chest Decoction). From chest and diaphragm directly to intestines and stomach. Urgently purge from below. No herb is used to moderate its potency. This is the most fierce and harsh formula. Hence called "Da" (Major). The Classic states: Taiyang Bing (Taiyang Disease). Pulse floating and moving-numerous. Floating indicates Wind. Numerous indicates Heat. Moving indicates Pain. Numerous also indicates Deficiency. Headache, fever, slight night sweating but contrary aversion to cold indicates exterior not resolved. Physician wrongly applies purgation. Moving-numerous pulse changes to slow. Diaphragm interior rejects pain. Stomach cavity empty. External pathogenic factor agitates diaphragm. Shortness of breath, irritability. Heart center feels stifled. Yang pathogenic factor sinks inward. Epigastrium becomes hard. Thus forms Jie Xiong (Chest Binding Syndrome). Da Xianxiong Tang (Major Trapping Chest Decoction) governs it. Commentary notes that the thirty-six characters describing the change from moving-numerous to slow depict the state of Jie Xiong (Chest Binding Syndrome) vividly. Generally, moving-numerous is the pulse for impending transmission; slow indicates transmission cannot resume. Yang pathogenic factor, due to erroneous purgation, sinks inward. Internal fluid retention then conflicts with it. Epigastrium becomes hard. Diaphragm interior rejects pain. Although this formula uses Natrii Sulfas and Rhubarb Radix et Rhizoma, the key lies entirely in the single herb, powdered Kansui Radix. It causes the sunken Yang pathogenic factor and the conflicting Yin fluid pathogenic factor to decompose from the diaphragm. Only then can Natrii Sulfas and Rhubarb Radix et Rhizoma achieve their purgative function. Without Kansui Radix, it belongs to Chengqi Fa (Chengqi Method), and does not constitute Xianxiong Tang (Trapping Chest Decoction).
Again, the Classic states: Shanghan (Cold Damage) for ten-plus days. Heat binds internally. Recurrent alternating chills and fever occur. Give Chaihu Shugan San? No, Da Chaihu Tang (Major Bupleurum Decoction). If Jie Xiong (Chest Binding Syndrome) has no significant heat, this is Water Binding in chest and diaphragm. Only slight head sweating occurs. Da Xianxiong Tang (Major Trapping Chest Decoction) governs it. Observing this clause: Water binding in chest and hypochondrium, yet still governing with this formula, relies entirely on the water-draining efficacy of Kansui Radix.
Rhubarb Radix et Rhizoma (0.5 jin, peeled) Lepidii Semen (0.5 jin, processed by heating) Natrii Sulfas (0.5 jin) Apricot Seed (0.5 jin, peeled, tips removed, processed until black)
The above four herbs. Pound and sieve two herbs. Add Apricot Seed and Natrii Sulfas. Grind together until pasty. Mix into powder. Take one pill-sized piece (size of a bullet). Separately pound powdered Kansui Radix 1 qian bi. White Honey 2 he. Water 2 sheng. Decoct to obtain 1 sheng. Take warm in one dose. Bowel movement occurs after one night. If no bowel movement, administer again. Bowel movement indicates efficacy. Prohibitions follow standard medication rules.
Jie Xiong (Chest Binding Syndrome) patients also have stiff necks. Resembling Rou Ji (Soft Spasm) condition. Purgation brings relief. Yi Da Xianxiong Wan (Suitable Major Trapping Chest Pill). Commentary notes: When Jie Xiong (Chest Binding Syndrome) progresses to stiff neck, chest binding is extremely tight. Turbid pathogenic factor fills the chest, ascending and obstructing. Body fluids fail to circulate. Tendons and vessels lose nourishment. Hence resembling Rou Ji (Soft Spasm). Pathogen occupies the upper region. Treatment method should be severe purgation. But Tang Decoction (Decoction) tends directly to lower jiao. Must change Tang Decoction to Wan (Pill). Decoct and take with dregs. Let it linger at the disease site. Act from top to bottom. Match the pathogen. Binding naturally resolves.
Yu Jiayan stated: Using Rhubarb Radix et Rhizoma, Kansui Radix, and Natrii Sulfas in the formula is indeed fierce. Furthermore adding Lepidii Semen and Apricot Seed to shoot Lung pathogenic factor upward and relieve urgency. During decoction, double the amount of White Honey to make it lingering, moistening, and guiding downward, thereby slowing the action. One must understand this intent to know the subtlety of usage.