治阳明病潮热。大便难。脉沉而滑。及内实腹痛者。此方主之。（内台方。原文
大黄（四两） 浓朴（二两 炙。去皮。） 枳实（三枚 炙。）
上三味。以水四升。煮取一升二合。去滓。分温二服。初服汤。当更衣。不尔者。尽饮
之。
歌曰 朴二枳三四两黄。小承微结好商量。长沙下法分轻重。妙在同煎切勿忘。
男元犀按。三承气俱阳明之正方。调胃承气。其方已载于太阳篇。故不复列。伤寒论云。
阳
也。胃络上通于心。阳明之燥火与少阴之君火相合。故心烦。可与此汤。解见太阳本方下。
至于大承气。取急下之义。阳明谵语潮热。胃中有燥屎五六枚。及二阳并病潮热。及阳明下
后心中懊 而烦。胃有燥屎。及大下后六七日不大便。烦不解。腹满痛。此有燥屎。及少阴
证口燥咽干。或自利清水色纯青等证。俾奏功于顷刻。小承气取微和胃气勿令大泄下之义。
阳明病热未潮。大便不硬。恐有燥屎。少与此汤转矢气者。可与大承气攻之。若不转矢气者
不与。及太阳病吐下发汗微烦。小便数。大便因硬者。令邪去而正不伤。论中逐条俱有深义。
张令韶云。胃与大肠小肠交相贯通者也。胃接小肠。小肠接大肠。胃主消磨水谷。化其精微
。内灌溉于脏腑。外充溢于皮毛。其糟粕下入于小肠。小肠受其糟粕复加运化。传入于大肠
。大肠方变化传道于直肠而出。故曰。小肠者。受盛之官。化物出焉。大肠者。传道之官。
变化出焉。是大承气者。所以通泄大肠而上承热气者也。故用朴实以去留滞。大黄以涤腐秽
。芒硝上承热气。小承气者。所以通泄小肠而上承胃气者也。故曰微和胃气。是承制胃府太
过之气者也。不用芒硝而亦名承气者以此。若调胃承气。乃调和胃气而上承君火之热者也。
以未成糟粕。故无用枳、朴之消留滞。此三承气之义也。承者制也。谓制其太过之气也。故
曰。亢则害承乃制。
柯韵伯曰。诸病皆因于气。秽物之不去。由于气之不顺也。故攻积之剂。必用气分之药。
因
是气药为臣。名小承气。味多性猛。制大其服。欲令大泄下也。味寡性缓。制小其服。欲微
和胃气也。大小之分以此。且煎法更有妙义。大承气用水一斗。煮枳、朴取五升。内大黄再
煮。取二升。去滓内芒硝。何哉。盖生者气锐而先行。熟者气钝而和缓。仲景欲使芒硝先化
燥屎。大黄继通地道。而后枳、朴除其痞满。若小承气以三味同煎。不分次第。同一大黄而
煎法不同。此可见微和之义也。
按张宪公云。承者。以卑承尊而无专成之义。天尊地卑。一形气也。形统于气。故地统
于天
化糟粕。运精微。而成传化之府。岂专以块然之形亦惟承此干行不息之气耳。汤名承气。确
有取义。非取顺气之义也。宪公此解。超出前人惜其所着伤寒类疏。未刊行世。宪公讳孝培。
古吴人也。
治疗阳明病，出现定时发热（潮热），大便困难，脉象沉而滑，以及体内实邪积聚导致腹痛的患者，此方主治。（出自《内台方》，原文如下）
大黄（四两） 厚朴（二两，炙过，去皮。） 枳实（三枚，炙过。）
以上三味药，用四升水，煮取一升二合药液，滤去药渣。分两次温服。初次服用汤药后，应当排便；如果未排便，则将剩余药液全部喝完。
歌诀曰：厚朴二两、枳实三枚、大黄四两。小承气汤适用于轻微结滞的情况，需仔细斟酌。长沙医派的下法分为轻重不同层次，其精妙之处在于同煎之法，切勿忘记。
陈元犀按语：三个承气汤都是治疗阳明病的正治方剂。调胃承气汤的方子已经在太阳篇中记载过了，所以这里不再列出。《伤寒论》说：“阳明病，若胃气不和，谵语者，少与调胃承气汤。”胃的络脉向上通于心，阳明的燥火与少阴的君火相合，所以会出现心烦症状，可以给予此汤治疗。详细解释见太阳篇本方下的注解。
至于大承气汤，取其急下存阴的意义。适用于阳明病出现谵语、潮热，胃中有干燥的粪便五六枚，以及太阳阳明并病出现潮热，以及阳明病攻下后心中懊恼而烦，胃中有燥屎，以及大泻下后六七天不大便，烦躁不解，腹部胀满疼痛，这是有燥屎的表现，以及少阴证出现口燥咽干，或自利清水、颜色纯青等症状，以便在短时间内奏效。
小承气汤取其微微调和胃气，不令过度泻下的意义。适用于阳明病热势尚未达到潮热程度，大便不硬，但担心有燥屎存在，少量给予此汤，如果患者转放屁（矢气），则可以给予大承气汤攻下；如果不转放屁，则不可给予。以及太阳病经过吐法、发汗后出现轻微心烦，小便频数，大便因此变硬的情况，旨在使邪气去除而正气不受伤。《伤寒论》中的逐条论述都蕴含深意。
张令韶说：胃与大肠、小肠是相互贯通的。胃连接小肠，小肠连接大肠。胃主要负责消磨水谷，将其化为精微物质，向内灌溉脏腑，向外充盈皮毛。其中的糟粕向下进入小肠，小肠接受糟粕后再次进行运化，传入大肠。大肠才变化传导至直肠排出。所以说：“小肠是受盛之官，化物出焉；大肠是传道之官，变化出焉。”这就是大承气汤的作用，它通过通泄大肠来上承热气。所以用厚朴去除留滞，大黄涤除腐秽，芒硝上承热气。
小承气汤的作用是通泄小肠而上承胃气，所以说“微和胃气”。这是为了制约胃腑太过之气。之所以不用芒硝也名为承气汤，原因就在这里。至于调胃承气汤，则是调和胃气并上承君火之热的。因为此时尚未形成糟粕，所以不需要用枳实、厚朴来消除留滞。这就是三个承气汤的含义。“承”就是制约的意思，指制约太过之气。所以说：“亢则害，承乃制。”
柯韵伯说：各种疾病都源于气机问题，秽物不能去除，是由于气机不顺。所以攻积的药剂，必须使用理气分的药物。因此以气药为臣药，命名为小承气汤。味道多且药性猛烈，加大服用剂量，想要达到大幅泻下的效果；味道少且药性缓和，减小服用剂量，想要微微调和胃气。大小承气的区别在于此。而且煎煮方法更有精妙之处。大承气汤用水一斗，先煮枳实、厚朴取五升，再加入大黄继续煮，取二升，滤去药渣后加入芒硝。为什么呢？因为生药气锐而先行，熟药气钝而和缓。张仲景想让芒硝先化解燥屎，大黄随后通畅地道（肠道），然后枳实、厚朴消除痞满。如果是小承气汤，将三味药一起煎煮，不分先后次序。同样是使用大黄，但煎法不同，这可见“微和”的含义。
按：张宪公说：“承”，是以卑下承受尊贵，没有独自成就的意义。天高地卑，是一体的形气关系。形体统摄于气，所以地统摄于天。小肠和大肠转化糟粕，运化精微，成为传化之府。岂能仅仅看作是有形的器官？它们只是承受这不断运行的气罢了。汤剂命名为承气，确实有其取义，并非取顺应气机的意思。张宪公的这个解释，超出了前人，可惜他所著的《伤寒类疏》未曾刊行于世。张宪公名孝培，是古吴人。
Treats Yangming disease presenting with tidal fever (periodic fever), difficulty in defecation, a deep and slippery pulse, as well as internal excess causing abdominal pain; this formula is indicated. (From *Neitai Fang*, original text follows)
Da Huang (Cassiae Semen, Rhubarbi Radix et Rhizoma, 4 liang) Hou Po (Magnoliae Officinalis Cortex, 2 liang, processed by stir-frying, skin removed.) Zhi Shi (Aurantii Fructus Immaturus, 3 pieces, processed by stir-frying.)
The above three herbs are decocted in 4 sheng of water to obtain 1.2 sheng of liquid. Strain the dregs. Divide into two warm doses. After the initial dose, defecation should occur; if not, consume the remaining liquid entirely.
Song says: Two liang of Hou Po, three pieces of Zhi Shi, four liang of Da Huang. Xiao Chengqi Tang is suitable for slight accumulation, requiring careful consideration. The purgative methods in Changsha distinguish between heavy and light degrees; the subtlety lies in simultaneous decoction, do not forget.
Chen Yuanxi notes: All three Chengqi formulas are correct treatments for Yangming disease. Tiaowei Chengqi Tang was already recorded in the Taiyang chapter, so it is not listed here. *Shanghan Lun* states: "In Yangming disease, if the stomach qi is disharmonious and there is delirium, give a small amount of Tiaowei Chengqi Tang." The meridians of the Stomach connect upwards to the Heart. The dryness-fire of Yangming combines with the Ministerial Fire of Shaoyin, thus causing mental restlessness (xin fan); this soup can be given. See the explanation under the original formula in the Taiyang chapter.
As for Dachengqi Tang, it takes the meaning of urgent purging to preserve Yin. It is indicated for Yangming disease with delirium and tidal fever, where there are five or six pieces of dry feces in the Stomach/intestines, as well as concurrent Taiyang-Yangming disease with tidal fever, post-purgation of Yangming disease with mental restlessness and irritability, presence of dry feces in the stomach, post-heavy purgation with no bowel movement for six or seven days, unresolved irritability, abdominal fullness and pain indicating dry feces, as well as Shaoyin syndrome with dry mouth and throat, or spontaneous diarrhea of clear green water, etc., to achieve effect rapidly.
Xiao Chengqi Tang takes the meaning of slightly harmonizing Stomach qi without causing excessive purging. It is indicated when Yangming disease heat has not yet reached tidal fever stage, stool is not hard, but there is suspicion of dry feces; give a small amount of this soup. If the patient passes flatus (shi qi), Dachengqi Tang can be used to attack; if no flatus occurs, do not give it. Also indicated for Taiyang disease after vomiting and sweating leading to slight irritability, frequent urination, and consequently hard stool, aiming to expel pathogenic factors without injuring healthy qi. Each clause in the treatise contains profound meaning.
Zhanglingshao says: The Stomach, Large Intestine, and Small Intestine are mutually connected. The Stomach connects to the Small Intestine, which connects to the Large Intestine. The Stomach is responsible for digesting food and drink, transforming them into essence, nourishing the zang-fu internally, and filling the skin and hair externally. The waste enters the Small Intestine, which further transforms it and transmits it to the Large Intestine. The Large Intestine then changes and conducts it to the rectum for excretion. Thus it is said: "The Small Intestine is the official of reception and transformation, from which substances emerge. The Large Intestine is the official of transmission, from which changes emerge." This is why Dachengqi Tongxie Dachang er Shangcheng Reqi Ye (passes through the Large Intestine to convey heat upwards). Therefore, Hou Po is used to remove stagnation, Da Huang to cleanse filth, and Mangxiao to convey heat upwards.
Xiao Chengqi Tang functions to pass through the Small Intestine and convey Stomach qi upwards, hence it is said to "slightly harmonize Stomach qi." It controls the excessive qi of the Stomach fu. The reason it is named Chengqi despite not using Mangxiao is due to this. As for Tiaowei Chengqi Tang, it harmonizes Stomach qi and conveys the heat of Junhuo (Ministerial Fire) upwards. Since waste has not yet formed, there is no need for Zhi Shi and Hou Po to eliminate stagnation. This is the meaning of the three Chengqi formulas. "Cheng" means to control/restrain, referring to restraining excessive qi. Thus it is said: "When hyperactive, harm results; when restrained, balance is achieved."
Ke Yunbo says: All diseases arise from qi issues; the inability to remove turbid matter is due to qi stagnation. Therefore, agents that attack accumulations must use qi-moving herbs. Hence, qi herbs serve as deputy ministers, named Xiao Chengqi Tang. With many flavors and strong nature, large dosages are prepared to desire significant purging. With few flavors and mild nature, small dosages are prepared to desire slight harmonization of Stomach qi. The distinction between large and small lies here. Moreover, the decoction method holds subtle meaning. Dachengqi Tang uses one dou of water, boils Zhi Shi and Hou Po to obtain five sheng, adds Da Huang and boils again to obtain two sheng, strains, and adds Mangxiao. Why? Because raw herbs have sharp qi and act first, while cooked herbs have dull qi and act slowly. Zhang Zhongjing intended for Mangxiao to first dissolve dry feces, Da Huang to subsequently open the earth pathway (intestines), and then Zhi Shi and Hou Po to remove palpable fullness. In contrast, Xiao Chengqi Tang decocts all three herbs together without sequence. Although Da Huang is the same, the decoction method differs, revealing the meaning of "slight harmonization."
Note: Zhang Xiangong says: "Cheng" implies the lower receiving from the higher without independent achievement. Heaven is high, Earth is low; they share form and qi. Form is governed by qi, so Earth is governed by Heaven. The intestines transform waste and transport essence, becoming organs of transmission. How can they be viewed merely as solid forms? They only receive this continuously moving qi. The name Chengqi indeed has specific meaning, not merely meaning following qi. Zhang Xiangong's interpretation surpasses predecessors, but unfortunately his work *Shanghan Leishu* was not published. Zhang Xiangong, courtesy name Xiaopei, was from Guwu.