桂枝（三两去皮味辛温） 甘草（三两炙味甘平） 大枣（十二枚擘味甘温） 芍
药（六两味酸微寒） 生姜（三两切味辛温） 胶饴（一升味甘温）
上六味。以水七升。煮取三升。去滓、内胶饴。更上微火消解。温服一升。日三服。
呕家不可用建中汤。以甜故也。
建中者。建脾也。内经曰。脾欲缓。急食甘以缓之。胶饴大枣甘草之甘。以缓中也。
辛、润也。散也。荣卫不足。润而散之。桂枝生姜之辛。以行荣卫。酸、收也。泄
也。正气虚弱。收而行之。芍药之酸。以收正气。
成氏云。或谓桂枝汤解表而芍药数少。建中汤温里而芍药数多。何也。皮肤为近。则
制小其服。心腹为远。则制大其服。此所以为不同也。
伤寒中风。有柴胡证。但见一证便是。不必悉具。
柴胡证。是邪气在表里之间也。或胸中烦而不呕。或渴。或腹中痛。或胁下痞硬。
或心下悸。小便不利。或不渴。身有微热。或咳。但见一证。便宜与柴胡汤治之。不必
待其证候全具也。
凡柴胡汤病证而下之。若柴胡证不罢者。复与柴胡汤。必蒸蒸而振。却发热汗出而解。
邪在半表半里之间。为柴胡证。即未作里实。医便以药下之。若柴胡证仍在者。
虽下之。不为逆。可复与柴胡汤。以和解之。得汤。邪气还表者。外作蒸蒸而热。先经下。
里虚。邪气欲出。内则振振然也。正气胜。阳气生。却复发热。汗出而解也。
伤寒二三日。心中悸而烦者。小建中汤主之。
前条心下悸而烦。皆与柴胡汤。此条悸而烦。建中主之何也。前条悸而烦。以往来寒
热默默不食。自表传里之悸烦也。此条悸而烦。以邪气在表里。头疼发热之时而悸烦。
此里虚血气不胜其邪之故也。故与建中汤以温里。如此可悟。凡治悸烦之例也。
伤寒二三日。邪气在表。未当传里之时。心中悸而烦。是非邪气搏所致。心悸者。
气虚也。烦者。血虚也。以气血内虚。与小建中汤。先建其里。
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。
日数过多。累经攻下。而柴胡证不罢者。亦须先与小柴胡汤。以解其表。经曰。凡
柴胡汤疾证而下之。若柴胡证不罢者。复与柴胡者是也。呕止者。表里和也。若呕不止。
郁郁微烦者。里热已甚。结于胃中也。与大柴胡汤。下其里寒则愈。
桂枝（三两，去皮，味辛、性温） 甘草（三两，炙用，味甘、性平） 大枣（十二枚，掰开，味甘、性温） 芍药（六两，味酸、微寒） 生姜（三两，切片，味辛、性温） 胶饴（一升，味甘、性温）
以上六味药。用水七升。煮取三升药液。滤去药渣，加入胶饴。再用小火加热使其溶解。每次温服一升。每日服用三次。
所谓“建中”，即建立中气（脾胃之气）。《内经》说：脾脏喜好缓和，急需用甘味食物来缓和它。胶饴、大枣、甘草的甘味，用来缓和中焦之气。辛味，具有滋润和发散的作用。营卫之气不足时，通过滋润和发散来调理。桂枝、生姜的辛味，用来运行营卫之气。酸味，具有收敛和泄降的作用。正气虚弱时，通过收敛和引导来调理。芍药的酸味，用来收敛正气。
成无己说：有人问，桂枝汤用于解表，芍药用量较少；建中汤用于温里，芍药用量较多。为什么呢？皮肤部位较浅近，所以制方剂量较小；心腹部位较深远，所以制方剂量较大。这就是两者的不同之处。
伤寒或中风病，出现柴胡证（少阳病证候），只要见到其中一个证候即可，不必所有证候都具备。
柴胡证，是邪气处于半表半里之间。有的表现为胸中烦闷但不呕吐，有的口渴，有的腹中疼痛，有的胁下痞塞硬满，有的心下悸动、小便不利，有的不渴、身体有轻微发热，有的咳嗽。只要见到其中一个证候，就适宜给予柴胡汤治疗。不必等待其证候全部具备。
凡是柴胡汤病证误用攻下法治疗后，如果柴胡证没有消除的，再次给予柴胡汤，必然会出现全身蒸蒸发热并伴有振颤，随后发热出汗而病愈。
邪气在半表半里之间，属于柴胡证，此时尚未形成里实证，医生便用药攻下。如果柴胡证仍然存在，虽然经过攻下，也不属于逆证，可以再次给予柴胡汤，以和解少阳。服药后，邪气由里出表，外部表现为蒸蒸发热；此前经过攻下，导致里气虚弱，邪气欲出，内部则出现振颤。正气战胜邪气，阳气生发，随后发热出汗而病解。
前一条所述的心下悸动且烦乱，均给予柴胡汤。这一条所述的悸动且烦乱，为何由建中汤主治呢？前一条的悸烦，是由于往来寒热、默默不欲饮食，邪气自表传里导致的悸烦。这一条的悸烦，是因为邪气在表里之间，在头疼发热之时出现的悸烦。这是里虚、血气不能抵御邪气的缘故。所以给予建中汤以温补里虚。由此可以领悟，凡是治疗悸烦的法则。
伤寒二三日，邪气在表，尚未当传里的时期，心中悸动且烦乱，这不是邪气搏结所致。心悸，是气虚的表现；烦乱，是血虚的表现。由于气血内虚，给予小建中汤，先建立中气（固护里气）。
太阳病，病程已过十余日，反而被误用攻下法二三次。之后四五日，柴胡证仍在的，先给予小柴胡汤。如果呕吐不止，心下拘急不适，郁郁微烦的，说明病未解除，给予大柴胡汤攻下里实，则痊愈。
病程日久，多次被攻下，而柴胡证未消除的，也须先给予小柴胡汤，以解除半表半里之邪。经书说：凡是柴胡汤病证误用攻下法，如果柴胡证未消除的，再次给予柴胡汤，就是这个道理。呕吐停止的，说明表里调和。如果呕吐不止，郁郁微烦的，说明里热已盛，结聚于胃中。给予大柴胡汤，攻下里实热结则痊愈。
Cinnamon Twig (Guizhi, *Ramulus Cinnamomi*, three liang, bark removed, pungent and warm) Licorice Root (Gancao, *Radix Glycyrrhizae*, three liang, honey-fried, sweet and neutral) Jujube (Dazao, *Fructus Ziziphi Jujubae*, twelve pieces, broken open, sweet and warm) Peony Root (Shaoyao, *Radix Paeoniae Alba*, six liang, sour and slightly cold) Fresh Ginger (Shengjiang, *Rhizoma Zingiberis Recens*, three liang, sliced, pungent and warm) Maltose (Jiaoyi, *Saccharum*, one sheng, sweet and warm)
The above six ingredients. Use seven sheng of water. Decoct to obtain three sheng of liquid. Remove the dregs, add the maltose. Heat gently over a low fire until dissolved. Take one sheng warm. Three times daily.
Patients with vomiting should not use Jianzhong Tang (Middle-Building Decoction). This is because the sweet flavor may exacerbate vomiting.
"Jianzhong" refers to establishing the Middle Qi (Spleen and Stomach Qi). The *Neijing* states: "The Spleen desires relaxation; urgently use sweet substances to relax it." The sweetness of Jiaoyi, Dazao, and Gancao serves to relax the Middle Jiao. Pungent flavors have moistening and dispersing properties. When Ying and Wei Qi are insufficient, they are regulated through moistening and dispersing. The pungency of Guizhi and Shengjiang facilitates the circulation of Ying and Wei Qi. Sour flavors have astringent and draining properties. When Zheng Qi (Upright Qi) is weak, it is regulated through astringing and guiding. The sourness of Shaoyao serves to astringe Zheng Qi.
Cheng Wuji stated: Some ask why Guizhi Tang uses less Shaoyao for releasing the exterior, while Jianzhong Tang uses more Shaoyao for warming the interior. The reason is that the skin is superficial, so the dosage is smaller; the heart and abdomen are deep, so the dosage is larger. This is the difference between them.
In Shanghan or Zhongfeng diseases, if Chaihu Syndrome (Shaoyang Syndrome) appears, it is sufficient to observe just one symptom; it is not necessary for all symptoms to be present.
Chaihu Syndrome indicates pathogenic factors located between the exterior and interior. Symptoms may include vexation in the chest without vomiting, thirst, abdominal pain, fullness and hardness in the hypochondrium, palpitations with difficult urination, absence of thirst with slight fever on the body, or cough. If any one of these symptoms is observed, it is appropriate to administer Chaihu Tang (Bupleurum Decoction). There is no need to wait for the complete syndrome to manifest.
If a patient with Chaihu Tang indications undergoes purgative treatment erroneously, and the Chaihu Syndrome persists, administering Chaihu Tang again will likely result in intense heat sensation followed by chills, then fever and sweating, leading to resolution.
Pathogenic factors located between the exterior and interior constitute Chaihu Syndrome. At this stage, interior excess has not yet formed. If the physician erroneously applies purgatives, but the Chaihu Syndrome remains, this is not considered a counter-indication (Ni Zheng). Chaihu Tang can be administered again to harmonize the Shaoyang. After taking the decoction, as pathogenic factors return to the exterior, intense heat sensation occurs externally. Previously, purgatives caused interior deficiency; as pathogenic factors attempt to exit, internal chills occur. When Zheng Qi prevails and Yang Qi generates, fever and sweating ensue, resulting in recovery.
In Shanghan disease, two to three days after onset, if there are palpitations and vexation, Xiao Jianzhong Tang (Minor Middle-Building Decoction) is the primary treatment.
In the previous clause, palpitations and vexation were treated with Chaihu Tang. Why is Jianzhong Tang used here? In the previous case, the palpitations and vexation resulted from alternating chills and fever, silent desire to eat, and transmission of pathogenic factors from the exterior to the interior. In this case, the palpitations and vexation occur during headache and fever, when pathogenic factors are between the exterior and interior. This is due to interior deficiency where Blood and Qi cannot resist the pathogen. Therefore, Jianzhong Tang is given to warm and tonify the interior. From this, one can understand the general principle for treating palpitations and vexation.
Two to three days into Shanghan, when pathogenic factors are still at the exterior and have not yet transmitted to the interior, if there are palpitations and vexation, this is not caused by pathogenic collision. Palpitations indicate Qi deficiency; vexation indicates Blood deficiency. Due to interior deficiency of Qi and Blood, Xiao Jianzhong Tang is administered to first establish the interior.
In Taiyang Disease, after more than ten days, if the patient was erroneously subjected to purgative treatment two or three times, and four to five days later the Chaihu Syndrome persists, first administer Xiao Chaihu Tang (Minor Bupleurum Decoction). If vomiting persists, there is urgency and discomfort in the epigastrium, and mild depression/vexation, indicating the disease has not resolved. Administer Da Chaihu Tang (Major Bupleurum Decoction) to purge the interior excess, which will lead to cure.
If the duration of the disease is prolonged and multiple purgative treatments have been applied, yet the Chaihu Syndrome persists, one must first administer Xiao Chaihu Tang to resolve the exterior/interior conflict. As stated in the classics: "For diseases requiring Chaihu Tang, if purgatives are used erroneously and the Chaihu Syndrome does not cease, re-administer Chaihu Tang." If vomiting ceases, it indicates harmony between the exterior and interior. If vomiting persists along with depression and vexation, it indicates severe interior heat accumulating in the Stomach. Da Chaihu Tang should be administered to purge the interior heat excess, leading to recovery.