【纲】仲景曰。伤寒表不解。心下有水气。干呕发热而咳。或渴。或利。或噎。或小便不利少
腹满。或喘者。小青龙汤。
【目】朱肱曰。问有干呕者何也。答曰。大凡呕者。饮食不下。干呕者。今人所谓 也。或因
汗出。或因有水。或因下利。脾胃有热。故使干呕。宜官局桔梗汤最佳。仲景治汗自出干呕者。桂
枝症也。身凉汗出。两胁痛。干呕者。十枣汤也。少阴不利脉微。与白通汤。利不止。厥逆无脉。
干呕烦者。白通加猪胆汁汤也。少阴下利。里寒外热。脉微欲绝。干呕者。通脉四逆汤也。干呕吐
涎沫头痛者。吴茱萸汤也。
张元素曰。或问小青龙与小柴胡症。皆呕而发汗。表里之症。大概仿佛。何故二方用药之不同。
曰。伤寒表不解。里热
未甚。不渴。欲饮水不能多。不当与之。以腹中热尚少而不能消水。停饮蓄积故作诸症。然水寒作
病。非温热不能解。故用小青龙。发汗散水。原其理初无里症。因水寒以致然也。夫小柴胡症。系伤
寒发热。热邪传入。在于半表半里之间。热气内攻。故生诸症。缘二症虽曰表里俱病。其中寒热不
同。故用药有姜、桂、柴、苓之不同也。
陶华曰。干呕者。空呕而无物出者也。大抵热在胃脘。与谷气并热。热气上熏。心下痞结则有
此症。太阳汗出干呕。桂枝汤。主自汗也。少阴下利干呕。姜附汤。主下利也。厥阴吐沫干呕。吴
萸汤。主涎沫也。邪去则吐自止矣。至如水气二症。又当以表里别之。伤寒表不解而心下有水气。
干呕。身热微喘。或自利者。小青龙汤主之。不发热但恶寒。咳而利。干呕者。亦水气也。十枣汤
下之。
【纲】张仲景说：伤寒表证未解，心下有停饮（水液代谢失常积聚于心下），出现干呕、发热且咳嗽。或者口渴，或者腹泻，或者咽喉噎塞感，或者小便不利且小腹胀满，或者气喘的，用小青龙汤治疗。
【目】朱肱说：问：为什么会有干呕的情况？答：大凡呕吐，是指饮食无法下行；干呕，就是现在人们所说的“哕”（呃逆或干呕）。这可能是因为出汗后所致，也可能是因为有水饮内停，或者是由于腹泻导致脾胃有热，从而引起干呕。适宜使用官方局方桔梗汤，效果最佳。张仲景治疗因汗出而干呕的，属于桂枝汤证（桂枝汤主治的太阳中风表虚证）。身体凉爽且汗出，两胁疼痛，伴有干呕的，用十枣汤治疗。少阴病脉象微弱，给予白通汤治疗；若腹泻不止，四肢厥冷且无脉，伴有干呕和心烦的，用白通加猪胆汁汤治疗。少阴病下利，表现为里寒外热，脉微欲绝，伴有干呕的，用通脉四逆汤治疗。干呕并吐出清稀涎沫且头痛的，用吴茱萸汤治疗。
张元素说：有人问小青龙汤证与小柴胡汤证，都表现为呕吐且需要发汗，表里症状大致相似，为什么这两个方剂的用药不同？回答说：伤寒表证未解，里热尚不严重，口不渴，想喝水但不能多喝，此时不应当直接给水喝，因为腹中热气尚少，不能运化水液，导致水饮停聚蓄积，从而产生各种症状。然而，水寒之邪致病，非温热药不能解除，所以使用小青龙汤，通过发汗来散除水饮。推究其原理，起初并没有里证，是因为水寒之邪导致如此。至于小柴胡汤证，是伤寒发热，热邪传入，位于半表半里之间，热气向内攻冲，从而产生各种症状。虽然这两种病症都说表里同病，但其中的寒热性质不同，因此用药在生姜、桂枝、柴胡、茯苓等方面有所不同。
陶华说：干呕，是指空呕而没有实物吐出的情况。大体上是热邪在胃脘部，与谷气相结合产生热，热气向上熏蒸，导致心下痞结，从而出现这种症状。太阳病汗出而干呕，用桂枝汤治疗，主要解决自汗问题。少阴病下利而干呕，用姜附汤（干姜、附子组成的温里剂）治疗，主要解决下利问题。厥阴病吐涎沫且干呕，用吴茱萸汤治疗，主要解决涎沫问题。邪气去除则呕吐自然停止。至于像水气引起的两种症状，又应当根据表里来区分。伤寒表证未解且心下有停饮，出现干呕、身热微喘，或者自发性腹泻的，用小青龙汤主治。如果不发热只恶寒，咳嗽且腹泻，伴有干呕的，也是水气为患，用十枣汤攻下治疗。
[General Principle] Zhang Zhongjing stated: When the exterior syndrome of Cold Damage (Shanghan) is not resolved, and there is fluid retention in the epigastrium (accumulation of pathological fluids below the heart), presenting with dry retching (gan ou), fever, and cough. Or if there is thirst, or diarrhea, or a sensation of choking in the throat, or difficulty in urination with fullness in the lower abdomen, or wheezing, Xiao Qing Long Tang (Minor Blue Dragon Decoction) should be used.
[Detailed Discussion] Zhu Gong asked: Why does dry retching occur? The answer is: Generally speaking, vomiting refers to the inability of food and drink to descend. Dry retching is what people today call "yue" (hiccups or dry heaving). It may be caused by sweating, or by the presence of internal fluid retention, or due to diarrhea leading to heat in the Spleen and Stomach, thus causing dry retching. The best treatment is the Ju Geng Tang (Platycodon Decoction) from the Imperial Pharmacy Bureau. Zhang Zhongjing treated cases of dry retching accompanied by spontaneous sweating as Gui Zhi Tang syndrome (a Taiyang wind-strike deficiency syndrome). Cases with a cool body, spontaneous sweating, pain in both hypochondria, and dry retching are treated with Shi Zao Tang (Ten Jujube Decoction). In Shaoyin disease with a faint pulse, Bai Tong Tang (White Pass Decoction) is administered; if diarrhea persists, cold limbs occur, the pulse becomes imperceptible, and dry retching with irritability appears, Bai Tong Jia Zhu Dan Ye Tang (White Pass Decoction plus Pig Bile) is used. For Shaoyin diarrhea characterized by interior cold and exterior heat, an imperceptible pulse, and dry retching, Tong Mai Si Ni Tang (Pulse-Returning Four Reversal Decoction) is indicated. For dry retching with expulsion of clear saliva and headache, Wu Zhu Yu Tang (Evodia Decoction) is prescribed.
Zhang Yuansu said: Someone asked why the formulas for Xiao Qing Long Tang syndrome and Xiao Chai Hu Tang syndrome differ, given that both present with vomiting and require sweating, and their exterior-interior symptoms are largely similar. The response is: In Cold Damage where the exterior is unresolved but interior heat is not severe, the patient is not thirsty, or desires water but cannot drink much. Water should not be given directly because the interior heat is insufficient to transform fluids, leading to fluid retention and accumulation, which causes various symptoms. However, diseases caused by cold-fluid require warm-hot herbs to resolve; therefore, Xiao Qing Long Tang is used to induce sweating and disperse fluid retention. Fundamentally, there was no interior syndrome initially; it resulted from cold-fluid pathogens. Regarding Xiao Chai Hu Tang syndrome, it involves Cold Damage fever where heat pathogens have transmitted to the half-exterior half-interior region. Heat attacks inward, generating various symptoms. Although both syndromes involve exterior and interior pathology, their cold-heat natures differ; hence, the use of herbs like Sheng Jiang (Zingiberis Rhizoma Recens), Gui Zhi (Cinnamomi Ramulus), Chai Hu (Bupleuri Radix), and Fu Ling (Poria) varies.
Tao Hua said: Dry retching refers to empty vomiting without material expulsion. Generally, this occurs when heat resides in the Stomach Epigastrium, combining with grain qi to generate heat. This heat steams upward, causing stagnation in the epigastrium, leading to this symptom. For Taiyang syndrome with spontaneous sweating and dry retching, Gui Zhi Tang (Cinnamon Twig Decoction) is used to address the spontaneous sweating. For Shaoyin syndrome with diarrhea and dry retching, Jiang Fu Tang (Ginger and Aconite Decoction) is used to address the diarrhea. For Jueyin syndrome with expulsion of saliva and dry retching, Wu Yu Tang (Evodia Decoction) is used to address the saliva. Once the pathogen is eliminated, vomiting ceases naturally. As for the two types of fluid-retention syndromes, they must be distinguished by exterior-interior differentiation. For Cold Damage with unresolved exterior and fluid retention in the epigastrium, presenting with dry retching, slight fever, mild wheezing, or spontaneous diarrhea, Xiao Qing Long Tang is the primary treatment. If there is no fever but only aversion to cold, accompanied by cough, diarrhea, and dry retching, this is also due to fluid retention, and Shi Zao Tang (Ten Jujube Decoction) should be used to purge it.