黄连一两 半夏（洗）半筋 栝蒌实（大者）一枚
右三味，以水六升，先煮栝蒌，取三升，去滓，内诸药，煮取二升，去滓，分温三服
。
【方解】
黄连涤热，半夏导饮，栝蒌润燥下行，合之以涤胸膈痰热，开胸膈气结；攻虽不峻，
亦能突围而入，故名小陷胸汤。分服三服，乃缓以治上之法也。
伤寒六、七日，结胸热实，脉沉而紧，心下痛，按之石□者，大陷胸汤主之
【注】
伤寒表不解，误下成痞，此其常也。伤寒或有因误下而成结胸者，乃其变也。今伤寒
六七日，结胸不因误下而成此热实之证，若脉沉紧，里实脉也。心下痛，按之右□，
里实证也。此为脉病皆实，故以大陷胸汤主之也。
【集注】
喻昌曰：「热实」二字，形容结胸之状甚明，见邪热填实于胸而不散漫也。浮紧主伤
寒无汗，沉紧主伤寒结胸，此与中风之阳邪结胸回别，所以不言浮也。又曰：阳邪误
下成结胸，阴邪误下成痞。然中风间有痞证，伤寒间有结胸证，又不可不知。
程应旄曰：虽曰阳邪内陷，然「阴阳」二字从虚实寒热上区别，非从中风伤寒上区别
。表热盛实转入胃府，则为阳明证；表热盛实不转入胃府，而陷入于膈，则为结胸证
。故不必误下始成也。不因下而成结胸者，必其人胸有燥邪，以失汗而表邪合之，遂
成里实。观此条曰：伤寒六、七日，又曰：脉沉而紧，则可知矣。
汪琥曰：或问脉沉紧，焉知非寒实结胸？答曰：胸中者，阳气之所聚也。邪热当胸而
结直至心下，石□且痛，则脉不但沉紧，甚至有伏而不见者，乌可以脉沉紧为非热耶
？大抵辨结胸之法，但当证书最为有准。
寒实结胸，无热证者，与三物（小陷胸汤），白散（亦可服）。
【按】
无热证之下，与三物小陷胸汤，当是「三物白散」，「小陷胸汤」四字，必是传写之
误。桔梗、贝母、巴豆三物，其色皆白，有三物白散之义，温而能攻，与寒实之理相
属；小陷胸汤，乃栝蒌、黄连，皆性寒之品，岂可以治寒实结胸之证乎？「亦可服」
三字，亦衍文也。
【注】
结胸证，身无大热，口不燥渴，则为无热实证，乃寒实也，与三物白散。然此证脉必
当沉紧。若脉沉迟或证见三阴，则又非寒实结胸可比，当以枳实理中汤治之矣。
【集注】
王肯堂曰：热实结胸，及寒实结胸，『活人书』不拘寒热，但用陷胸汤，不差者用枳
实理中丸，即应手而愈。
方有执曰：寒以饮言，饮本寒也，又得水寒，两寒搏结而实于胸中，故谓无热证也。
程知曰：结胸有大小之别，寒热之异，不得概用硝黄也。
郑重光曰：水寒结实在胸，则心阳被据，自非细故，用三物白散下寒而破结，皆不得
已之兵也。
Coptidis Rhizoma (Huanglian) 1 liang, Pinelliae Tuber (Banxia) half sheng (washed), Trichosanthis Fructus (Gualou Shi) one large fruit.
The above three ingredients: Use six sheng of water, first decoct the Trichosanthis Fructus until reduced to three sheng, remove the dregs, add the remaining herbs, and decoct until two sheng remain. Remove the dregs and divide into three warm doses.
[Fangjie - Formula Analysis]
Coptidis Rhizoma clears heat; Pinelliae Tuber guides phlegm-fluids downward; Trichosanthis Fructus moistens dryness and directs the action downward. Combined, they clear phlegm-heat from the chest and diaphragm and open qi stagnation in the chest and diaphragm. Although the purgative force is not severe, it can break through obstructions to reach the disease site, hence named Xiao Xianxiong Tang (Minor Chest-Penetrating Decoction). Dividing the dose into three administrations is a method of treating upper-body conditions gently.
In Shaoyang disease (Taiyang disease), after six or seven days, if there is Jie Xiong (Chest-Knotting) with heat and excess syndrome, characterized by a deep and tight pulse, pain in the epigastrium, and hardness upon palpation like stone, Da Xianxiong Tang (Major Chest-Penetrating Decoction) is indicated.
[Annotation]
When Taiyang exterior syndrome is unresolved and mistaken purgation leads to Pi (Glomus/Fullness), this is the common pattern. However, sometimes mistaken purgation in Taiyang disease leads to Jie Xiong, which is a variation. In this case, after six or seven days of Taiyang disease, Jie Xiong arises not from mistaken purgation but forms a heat-excess syndrome. A deep and tight pulse indicates interior excess. Pain in the epigastrium with hardness upon palpation indicates interior excess. Since both the pulse and symptoms indicate excess, Da Xianxiong Tang is used.
[Collected Annotations]
Yu Chang stated: The term "Heat Excess" clearly describes the state of Jie Xiong, indicating that pathogenic heat fills the chest without dissipating. A floating-tight pulse indicates Taiyang disease with no sweating; a deep-tight pulse indicates Taiyang Jie Xiong. This differs distinctly from Yang-pathogen Jie Xiong in Wind-Stroke, hence the floating pulse is not mentioned. He further said: Yang-pathogen mistaken purgation leads to Jie Xiong; Yin-pathogen mistaken purgation leads to Pi. However, Wind-Stroke may occasionally present with Pi, and Taiyang disease may occasionally present with Jie Xiong, which must be known.
Cheng Yingmao stated: Although it is said that Yang-pathogen sinks inward, the distinction between "Yin and Yang" is based on deficiency/excess and cold/heat, not on Wind-Stroke vs. Cold-Injury. If exterior heat becomes excessive and enters the Stomach Fu, it becomes Yangming Syndrome; if it does not enter the Stomach Fu but sinks into the Diaphragm, it becomes Jie Xiong Syndrome. Thus, mistaken purgation is not required for Jie Xiong to form. When Jie Xiong forms without mistaken purgation, it implies the person has dryness-pathogen in the chest; due to failure to sweat, the exterior pathogen combines with it, resulting in interior excess. The mention of "six or seven days" and "deep-tight pulse" confirms this.
Wang Hu stated: One might ask how we know a deep-tight pulse is not Cold-Excess Jie Xiong? The answer is: The chest is where Yang Qi gathers. If pathogenic heat knots in the chest extending to the epigastrium, causing hardness like stone and pain, the pulse may be not only deep-tight but even hidden and invisible. How can one assume it is not heat just because the pulse is deep-tight? Generally, the most accurate method to differentiate Jie Xiong is to rely on symptoms.
For Cold-Excess Jie Xiong without heat signs, Sanwu Baisan (Three-Ingredient White Powder) is given (or Xiao Xianxiong Tang may also be taken).
[Commentary]
The phrase "give Sanwu Xiao Xianxiong Tang under 'no heat signs'" contains an error. "Sanwu Xiao Xianxiong Tang" should be "Sanwu Baisan"; "Xiao Xianxiong Tang" is likely a transcription error. Jiegeng (Platycodonis Radix), Beimu (Fritillariae Bulbus), and Badou (Crotonis Semen) are all white, fitting the meaning of Sanwu Baisan. It is warm and purgative, matching the pathology of Cold-Excess. Xiao Xianxiong Tang consists of Gualou and Huanglian, both cold-natured substances; how could it treat Cold-Excess Jie Xiong? The words "may also be taken" are likely interpolations.
[Annotation]
If Jie Xiong presents with no significant fever and no dry mouth/thirst, it is a non-heat excess syndrome, i.e., Cold-Excess, treated with Sanwu Baisan. However, the pulse must be deep-tight. If the pulse is deep-slow or symptoms involve the Three Yin meridians, it cannot be compared to Cold-Excess Jie Xiong and should be treated with Zhishi Lizhong Tang.
[Collected Annotations]
Wang Kentang stated: For Heat-Excess Jie Xiong and Cold-Excess Jie Xiong, *Ren Shu* (Book of Human Life) uses Xianxiong Tang regardless of cold or heat; if ineffective, Zhishi Lizhong Wan is used, resulting in immediate recovery.
Fang Youzhi stated: Here, "Cold" refers to fluid retention; fluids are inherently cold. Combined with external cold, the two colds knot together in the chest, hence termed "no heat signs."
Cheng Zhi stated: There are differences in size (Major/Minor) and nature (Cold/Heat) among Jie Xiong cases; one cannot indiscriminately use Xiaoshi (Miris Natri Sulfas) and Dahuang (Rhei Radix et Rhizoma).
Zheng Zhongguang stated: When cold-water knots firmly in the chest, Heart Yang is occupied, which is no trivial matter. Using Sanwu Baisan to purge cold and break knots is a measure of last resort.