太阳居三阳之表，其病过经不解，不转属阳明，则转少阳矣。心烦喜呕，为柴胡证。然柴胡证或胸中烦而
不痛，或大便微结而不溏，
或腹中痛而不满。此则胸中痛，大便溏，腹微满，皆不是柴胡证。但以欲呕一证似柴胡，当深究其欲呕之故矣。
夫伤寒中风，有柴胡证，有半表证也，故呕而发热者主之。此病既不关少阳寒热往来、胁下痞硬之半表，见太阳
过经而来，一切皆属里证，必十日前吐下而误之坏病也。胸中痛者，必极吐可知；腹微满，便微溏，必误下可
知。是太阳转属阳明，而不属少阳矣。今胃气虽伤，而余邪未尽，故与调胃承气和之。不用枳、朴者，以胸中
痛、上焦伤，即呕多虽有阳明证，不可攻之谓也。若未经吐下，是病气分而不在胃。则呕不止而郁郁微烦者，
当属之大柴胡矣。
此阳明少阳疑似证。前条得坏病之虚，此条得坏病之实。
上论柴胡变证。
太阳病过经十余日，反二三下之，后四五日，柴胡证仍在者，先与小柴胡汤。呕不止，心下急，郁郁微烦者，
为未解也，与大柴胡汤下之则愈。
病从外来者，当先治外而后治其内。此屡经妄下，半月余而柴胡证仍在。因其人不虚，故枢机有主而不为
坏病。与小柴胡和之，表证虽除，内尚不解。以前此妄下之药，但去肠胃有形之物，而未泄胸膈气分之结热也。
急者满也，但满而不痛，即痞也。姜、夏以除呕，柴、芩以去烦，大枣和里，枳芍舒急。而曰下之则愈者，见大
柴胡为下剂，非和剂也。若与他药和下之，必有变证，意在言外。呕不止，属有形；若欲呕，属无形。
伤寒十余日，热结在里，复往来寒热者，与大柴胡汤。
里者对表而言，不是指胃。此热结气分，不属有形，故十余日复能往来寒热。若热结在胃，则蒸蒸发热，不
复知有寒矣。往来寒热，故倍生姜佐柴胡以解表；结热在里，故去参、甘之温补，加枳、芍以破结。
伤寒发热，汗出不解，心下痞硬，呕吐而下利者，大柴胡汤主之。
汗出不解，蒸蒸发热者，是调胃承气证。汗出解后，心下痞硬、下利者，是生姜泻心证。此心下痞硬，协热
而利，表里不解，似桂枝人参证。然彼在妄下后而不呕，则此未经下而呕，则呕而发热者，
小柴胡主之矣。然痞硬在心下而不在胁下，斯虚实补泻之所由分也。故去参、甘之甘温益气，而加枳、芍之酸
苦涌泄耳。
上论大柴胡证。
大柴胡汤∶
小柴胡汤去人参、甘草，加生姜（二两），芍药（三两），枳实（四枚）。余同小柴胡法。
按∶大柴胡是半表半里气分之下药，并不言大便。其心下急与心下痞硬，是胃口之病，而不在胃中；结热
在里，非结实在胃。且下利则地道已通，仲景不用大黄之意晓然。若以“下之”二字，妄加大黄，则十枣汤“攻
之”二字，如何味乎？
大小柴胡，俱是两解表里，而有主和主攻之异。和无定体，故有加减；攻有定局，故无去取之法也。
太阳经位于三阳经的最表层，其病证若经过传变期限仍未解除，不转入阳明经，就会转入少阳经。心烦且喜呕，是柴胡汤证的典型表现。然而，柴胡汤证有时表现为胸中烦闷但不疼痛，有时大便微结而不稀溏，有时腹中疼痛但无胀满感。而本条所述则出现胸中疼痛、大便稀溏、腹部轻微胀满，这些都不是柴胡汤证的指征。仅仅因为“想要呕吐”这一症状与柴胡汤证相似，就应当深入探究其想要呕吐的原因。
在伤寒或中风病中，若有柴胡汤证，属于半表半里证，因此对于呕吐且发热的患者，主用柴胡汤治疗。此病既然不涉及少阳寒热往来、胁下痞塞硬满的半表证，而是见太阳病过经而来，一切症状皆归属于里证，这必定是前十日内因误用吐法或下法导致的坏病。胸中疼痛，必然是极度的催吐所致可知；腹部轻微胀满，大便微溏，必然是误用下法所致可知。这是太阳病转属阳明经，而不是转属少阳经。如今胃气虽然受损，但余邪未尽，所以给予调胃承气汤来调和胃气。不用枳实、厚朴的原因，是因为胸中疼痛、上焦受伤，即使用语出自《伤寒论》“呕多虽有阳明证，不可攻之”的原则，意指此时不可攻下。如果未经过吐下治疗，说明病气在气分而不在胃腑。那么呕吐不止且心中郁郁微烦的，应当归属为大柴胡汤证。
这是阳明病与少阳病的疑似证候。前一条论述的是获得坏病的虚证，本条论述的是获得坏病的实证。以上论述了柴胡汤的变证。
太阳病经过传变十余日，反而被误用了二三次下法，之后又过了四五日，柴胡汤证仍然存在，先给予小柴胡汤。若呕吐不止，心下拘急不适，心中郁郁微烦，说明病邪未解，应给予大柴胡汤攻下即可痊愈。
病邪从外侵入者，应当先治外而后治内。此处屡次误用下法，半月有余而柴胡汤证仍在。因为患者体质不虚，所以枢机功能有主而不致成为坏病。给予小柴胡汤和解，虽然表证已除，但内部尚未解开。这是因为之前误下的药物，只去除了肠胃中有形的积滞，而未宣泄胸膈间气分的郁热。“急”指的是胀满，仅胀满而不疼痛，就是痞证。生姜、半夏用来止呕，柴胡、黄芩用来除烦，大枣用来调和里气，枳实、芍药用来舒缓拘急。说“下之则愈”，是表明大柴胡汤属于下剂，而非和剂。如果与其他药物配合进行温和攻下，必然会产生变证，其深意在于言外。呕吐不止，属于有形之邪阻滞；若是欲呕，属于无形之气机不畅。
伤寒十余日，热邪结聚在里，同时又有往来寒热的症状，给予大柴胡汤。
这里的“里”是相对于“表”而言，并不是指胃腑。此处的热结在气分，不属于有形实邪，所以十余日后仍能出现往来寒热。如果热邪结聚在胃腑，则会表现为蒸蒸发热，不再知道有恶寒的感觉了。因为有往来寒热，所以加倍生姜辅助柴胡以解表；因为热结在里，所以去掉人参、甘草的温补性质，加入枳实、芍药以破结散滞。
伤寒发热，汗出后热不退，心下痞塞硬满，呕吐并伴有下利的，以大柴胡汤主治。
汗出后热不退，表现为蒸蒸发热的，是调胃承气汤证。汗出热解后，出现心下痞塞硬满、下利的，是生姜泻心汤证。此处心下痞塞硬满，协热而下利，表里同病，看似桂枝人参汤证。然而彼证是在误下之后且不呕吐，而此证未经误下却呕吐，若是呕吐且发热，应用小柴胡汤主治。但是痞硬的位置在心下而不在胁下，这就是虚实、补泻区别所在。所以去掉人参、甘草的甘温益气作用，而加入枳实、芍药的酸苦涌泄功效。以上论述了大柴胡汤证。
大柴胡汤方：
在小柴胡汤的基础上，去掉人参、甘草，加入生姜（二两），芍药（三两），枳实（四枚）。其余煎服方法同小柴胡汤法。
按语：大柴胡汤是作用于半表半里气分的下剂，文中并未提及大便情况。其“心下急”与“心下痞硬”，是胃口部位的问题，而不在胃腑之中；热结在里，并非结实在胃中。况且已有下利，说明肠道通路已通，张仲景不使用大黄的意思显而易见。如果凭借“下之”二字，妄自大黄，那么十枣汤中“攻之”二字该如何品味呢？
大柴胡汤与小柴胡汤，都是表里双解，但有主和解与主攻下的区别。和解没有固定的体例，所以有加减变化；攻下有固定的格局，所以没有去除或取舍药物的说法。
Taiyang (Sun Yang) resides on the exterior of the three Yang channels. If its disease persists beyond the transmission period without transferring to Yangming, it will transfer to Shaoyang. Mental restlessness and a propensity for vomiting are signs of Chaihu Syndrome. However, in Chaihu Syndrome, one may experience mental restlessness in the chest without pain, or slightly constipated stools without diarrhea, or abdominal pain without fullness. In this case, however, there is pain in the chest, loose stools, and slight abdominal fullness; none of these are indications for Chaihu Syndrome. Since only the symptom of "desire to vomit" resembles Chaihu Syndrome, one must deeply investigate the cause of this desire to vomit.
In Cold Damage or Wind Strike, if Chaihu Syndrome is present, it belongs to the Half-Exterior/Half-Interior syndrome. Therefore, for patients with vomiting and fever, [Chaihu Tang] is the primary treatment. This disease does not involve the Half-Exterior symptoms of Shaoyang, such as alternating chills and fever or hypochondriac stiffness and fullness. Instead, presenting as Taiyang disease persisting beyond its term, all symptoms belong to the Interior. This must be a *Huai Bing* (complicated disease caused by mismanagement) resulting from erroneous use of emetic or purgative therapies within the previous ten days. Pain in the chest indicates that excessive emesis was likely used; slight abdominal fullness and loose stools indicate that erroneous purgation was likely used. Thus, Taiyang has transferred to Yangming, not to Shaoyang. Although the Stomach Qi is now injured, residual pathogenic factors remain. Therefore, Tiaowei Chengqi Tang is given to harmonize. Zhi Shi (Immature Bitter Orange) and Hou Po (Magnolia Bark) are not used because, as stated in the text, "if there is much vomiting even with Yangming signs, one must not attack," implying that due to pain in the chest and injury to the Upper Jiao, purgation is contraindicated. If no emetic or purgative had been used previously, the pathogen would be in the Qi level rather than the Stomach organ. In such cases, persistent vomiting accompanied by mild depression and irritability would belong to Dahuang Huanglian Xiexin Tang or similar patterns, but specifically here, it points towards Dachaihu Tang.
This is a differential diagnosis between Yangming and Shaoyang diseases. The preceding clause discusses the deficiency aspect of *Huai Bing*, while this clause discusses the excess aspect. The above discusses the variations of Chaihu Syndrome.
If Taiyang disease persists for more than ten days after transmission, and is erroneously treated with purgatives two or three times, and after another four or five days, Chaihu Syndrome still remains, first administer Xiaochaihu Tang. If vomiting persists, there is urgency and tightness below the heart, and mild depression with irritability, the disease is unresolved; administer Dachaihu Tang to purge, and recovery will follow.
When pathogens come from outside, one should treat the exterior first and then the interior. Here, despite multiple erroneous purgations over more than half a month, Chaihu Syndrome remains. Because the patient's constitution is not deficient, the pivot mechanism has a master and does not become a *Huai Bing*. Administering Xiaochaihu Tang harmonizes the condition. Although the exterior signs are removed, the interior is still unresolved. This is because the previous erroneous purgatives only removed有形 (有形之物 - tangible/physical accumulation) in the intestines and stomach, but did not dissipate the heat constrained in the Qi level of the chest and diaphragm. "Urgency" refers to fullness; fullness without pain constitutes Pi (痞 - stuffiness/blockage). Shengjiang (Fresh Ginger) and Banxia (Pinellia Rhizome) remove vomiting; Chaihu (Bupleurum Root) and Huangqin (Scutellaria Root) remove irritability; Dazao (Jujube Fruit) harmonizes the interior; Zhishi (Immature Bitter Orange) and Shaoyao (Peony Root) relieve urgency. The phrase "purge to achieve cure" indicates that Dachaihu Tang is a purgative formula, not a harmonizing formula. If combined with other drugs for mild purgation, variable syndromes would inevitably arise; the intent lies beyond the words. Persistent vomiting belongs to tangible obstruction; desire to vomit belongs to intangible Qi dysfunction.
In Cold Damage lasting over ten days, if heat is constrained internally and there is also alternating chills and fever, administer Dachaihu Tang.
"Interior" here is relative to "Exterior" and does not refer specifically to the Stomach. This heat constraint is in the Qi level, not tangible matter, so alternating chills and fever can still occur after ten days. If heat were constrained in the Stomach, it would manifest as steaming fever, and one would no longer perceive chills. Due to alternating chills and fever, the dosage of Shengjiang is doubled to assist Chaihu in resolving the exterior; due to heat constraint in the interior, Ren Shen (Ginseng Root) and Gan Cao (Licorice Root) are removed to avoid warm tonification, and Zhishi (Immature Bitter Orange) and Shaoyao (Peony Root) are added to break up constraints.
In Cold Damage with fever, where sweating does not resolve the condition, accompanied by stuffiness and hardness below the heart, vomiting, and diarrhea, Dachaihu Tang is the primary treatment.
Sweating without resolution and steaming fever indicate Tiaowei Chengqi Tang syndrome. Resolution of fever after sweating, followed by stuffiness/hardness below the heart and diarrhea, indicates Shengjiang Xiexin Tang syndrome. Here, stuffiness/hardness below the heart with heat-collateralized diarrhea and unresolved exterior/interior resembles Guizhi Renshen Tang syndrome. However, that syndrome occurs after erroneous purgation without vomiting, whereas this case involves vomiting without prior purgation. If there were vomiting and fever, Xiaochaihu Tang would be indicated. However, the stuffiness/hardness is located below the heart, not in the hypochondrium, which distinguishes deficiency/excess and tonification/purgation. Therefore, Ren Shen (Ginseng Root) and Gan Cao (Licorice Root) are removed to avoid sweet-warm Qi tonification, and Zhishi (Immature Bitter Orange) and Shaoyao (Peony Root) are added for sour-bitter draining and purging effects. The above discusses Dachaihu Tang syndrome.
Dachaihu Tang:
Derived from Xiaochaihu Tang by removing Ren Shen (Ginseng Root) and Gan Cao (Licorice Root), adding Shengjiang (Fresh Ginger, 2 liang), Shaoyao (Peony Root, 3 liang), and Zhishi (Immature Bitter Orange, 4 pieces). The remaining preparation method follows Xiaochaihu Tang.
Note: Dachaihu Tang is a purgative acting on the Qi level of the Half-Exterior/Half-Interior; it does not mention bowel movements. "Urgency below the heart" and "stuffiness/hardness below the heart" are disorders of the stomach opening, not the Stomach organ itself; heat constraint in the interior is not solid accumulation in the Stomach. Furthermore, since diarrhea is present, the lower pathway is already open, making Zhang Zhongjing's intention to omit Da Huang (Rhubarb Root) clear. If one were to arbitrarily add Da Huang based on the word "purge," how would one interpret the word "attack" in Shizao Tang?
Both Dachaihu Tang and Xiaochaihu Tang resolve both exterior and interior, but one focuses on harmonizing and the other on attacking. Harmonization has no fixed form, hence modifications exist; attacking has a fixed pattern, hence there is no method of removal or selection.