桂枝（三两去皮） 芍药（六两） 甘草（二两炙） 生姜（三两切） 胶饴（一升） 大枣（十
一枚擘）
上六味。以水七升。煮取三升。去滓。纳胶饴。更上微火消解。温服一升。日三服。
此桂枝汤倍芍药而加胶饴也。本太阳表药。一转移而即变为安太阴之制。神化极矣。伤
寒二
三日。心中悸而烦者。中土虚馁。都城震恐。桂枝汤本主和营复阳。而但倍芍药加胶饴。奠
安中土。故曰建中。甘能满中。仍与桂枝汤同。故重申其禁曰。呕家不可用建中汤。以甜
故也。
伤寒阳脉涩。阴脉弦。腹中急痛者。先与小建中汤。盖阳脉涩。则中土已虚。阴脉弦
。则
木来贼土之象。腹中急痛。是脾阳下陷。此时若用小柴胡制木。其如中土先已虚馁何。夫中
土虚馁。非甘不补。土受木克。非酸不安。必先以小建中汤。扶植中土。土气既实。若不瘥
。再以小柴胡。疏土中之木。用药自有先后。非先以小建中姑为尝试也。
栀子（十二枚擘） 香豉（四两绵裹）
上二味。以水四升。先煮栀子。得二升半。纳豉煮取一升半。去滓。分为二服。温进一
服。得吐者止后服。
此非吐法之主方也。因误汗吐下后。正气已伤。邪留上焦。扰动阳气。因生烦热。无论
虚烦
实烦。皆宜此方取吐。虚烦者。若经中所指虚烦不得眠。反复颠倒。心中懊 。胃中空虚。
客气动膈。按之心下濡。舌上胎饥不能食。不结胸。但头汗出。皆虚烦之候也。实烦者。若
经中所指胸中窒。心中结痛。皆实烦之候也。此方主宣膈上之热。使得涌吐而解。若本有寒
分者不宜。故经有病患旧微溏不可与之戒。
今人用栀子俱炒黑。不能作吐。本方生用。故入口即吐也。香豉蒸 而成。性主上升。
故能载之以作吐。乃吐法中之轻剂也。
凡用吐法。当先审邪之高下。心下满而硬痛者。结胸证也。宜陷胸法。心下痞硬者。虚
痞也。宜泻心法。此则心中懊 。心中结痛。心下濡。故宜涌吐。毫厘千里。须当辨之。
桂枝（三两，去皮） 芍药（六两） 甘草（二两，炙） 生姜（三两，切） 胶饴（一升） 大枣（十枚，掰开）
以上六味药。用水七升。煮取三升。去渣。加入胶饴。再用微火加热使其溶解。每次温服一升。每日服用三次。
这是桂枝汤加倍芍药并加入胶饴而成的方剂。原本是治疗太阳表证的药物，一经转变就变成了安定太阴的方制。其变化之妙达到了极点。伤寒病二三天后，出现心中悸动且烦躁的症状，这是因为中焦脾胃虚弱，如同都城受到震动惊恐。桂枝汤原本主要作用是调和营卫、恢复阳气，但这里只是加倍芍药并加入胶饴，以奠定安固中焦脾胃之气。所以称为“建中”。甘味能补益中焦，这与桂枝汤的道理相同，因此再次重申其禁忌说：呕吐患者不可使用建中汤，因为甜味会助湿生痰的缘故。
伤寒病见阳脉涩、阴脉弦，腹中拘急疼痛的，先给予小建中汤。因为阳脉涩，说明中焦脾胃已经虚弱；阴脉弦，是肝木来克制脾土的征象。腹中拘急疼痛，是脾阳下陷的表现。此时如果用小柴胡汤来制约肝木，那对于已经虚弱的中焦脾胃该怎么办呢？中焦脾胃虚弱，非甘味不能补益；土受木克，非酸味不能安宁。必须先用小建中汤，扶持植立中焦脾胃之气。待土气充实后，如果病未痊愈，再使用小柴胡汤，疏解郁结在土中的木气。用药自有先后次序，并不是先用小建中汤姑且尝试一下。
以上两味药。用水四升，先煮栀子，煮至剩二升半时，加入香豉，继续煮取一升半。去渣。分为两次服用。温服一次。如果引起呕吐的，就停止服用剩下的药。
这并不是吐法的主方。而是因为误用汗、吐、下法之后，正气已经受损，邪气留滞在胸膈上焦，扰动阳气，因而产生烦热。无论是虚烦还是实烦，都适宜用此方通过涌吐来解除。所谓虚烦，如经文中所指出的虚烦不得眠，翻来覆去，心中懊恼，胃中空虚，客气扰动膈间，按压心下部柔软，舌苔薄而干燥不能进食，不形成结胸证，只有头部出汗，这些都是虚烦的候象。所谓实烦，如经文中所指出的胸中窒塞感，心中结痛，这些都是实烦的候象。此方主要宣散膈上的热邪，使其通过涌吐而解。如果患者本有寒湿分证的，就不适宜使用，所以经文有告诫：平素大便稀溏的患者不可给予此方。
现在的人使用栀子都是炒黑，不能引起呕吐。本方要求生用，所以入口即引起呕吐。香豉是经过蒸制的，药性主上升，所以能载引栀子作吐。这是吐法中的轻剂。
凡是使用吐法，应当先审察邪气的高下位置。如果心下部满闷且硬痛，是结胸证，适宜用陷胸法。如果心下部痞塞硬满，是虚痞证，适宜用泻心法。此处则是心中懊恼，心中结痛，心下部柔软，所以适宜用涌吐法。毫厘之差可能导致千里之谬，必须仔细辨别。
Cinnamon Twig (Guizhi, 3 liang, bark removed) White Peony Root (Baishao, 6 liang) Licorice Root (Gancao, 2 liang, honey-fried) Fresh Ginger (Shengjiang, 3 liang, sliced) Maltose (Jiaoyi, 1 sheng) Jujube (Dazao, 10 pieces, torn open)
Take the above six ingredients. Add seven sheng of water. Decoct to obtain three sheng. Remove the dregs. Add the maltose. Heat gently over a low fire until dissolved. Take one sheng warm. Administer three times daily.
This is Guizhi Tang (Cinnamon Twig Decoction) with doubled Baishao and added Jiaoyi. Originally a formula for treating Taiyang exterior syndromes, it transforms immediately into a regimen that stabilizes the Taiyin. Its transformation is extremely subtle. In Shaoyang disease, after two or three days, if there is palpitation and irritability in the heart, it indicates deficiency and weakness of the Middle Jiao (Spleen and Stomach), akin to a capital city shaken by fear. Guizhi Tang originally harmonizes Ying (Nutrient) Qi and restores Yang Qi; here, by merely doubling Baishao and adding Jiaoyi, it secures and anchors the Middle Jiao. Hence it is called "Jian Zhong" (Establishing the Middle). Sweet flavor can fill and tonify the Middle. The principle remains similar to Guizhi Tang, hence the contraindication is reiterated: patients prone to vomiting should not use Jianzhong Tang, due to the sweet nature.
In Shaoyang disease, if the Yang pulse is choppy (Se) and the Yin pulse is taut (Xian), accompanied by acute abdominal pain, first administer Xiao Jianzhong Tang. A choppy Yang pulse indicates existing deficiency of the Middle Jiao; a taut Yin pulse is a sign of Wood attacking Earth. Acute abdominal pain signifies sinking of Spleen Yang. At this time, if Xiaochaihu Tang were used to subdue Wood, what would be done about the already deficient Middle Jiao? Deficiency of the Middle Jiao cannot be tonified without sweet flavors; when Earth is overcome by Wood, it cannot be pacified without sour flavors. One must first use Xiao Jianzhong Tang to support and establish the Middle Jiao. Once the Qi of Earth is solid, if the condition does not resolve, then use Xiaochaihu Tang to vent the Wood stagnated within the Earth. There is a proper sequence in medication; it is not merely a trial with Xiao Jianzhong Tang first.
Gardenia Fruit (Zhizi, 12 pieces, torn open) Fermented Soybean (Xiangchi, 4 liang, wrapped in silk)
Take the above two ingredients. Add four sheng of water. First decoct Zhizi until two and a half sheng remain. Add Xiangchi and decoct to obtain one and a half sheng. Remove the dregs. Divide into two doses. Take one dose warm. If vomiting occurs, stop taking the remaining dose.
This is not the primary formula for emesis methods. It is used because after erroneous application of sweating, vomiting, or purging methods, the Righteous Qi (Zheng Qi) is damaged, pathogenic factors remain in the Upper Jiao (Chest/Diaphragm), disturbing Yang Qi and generating irritability and heat. Whether it is Empty Irritability (Xu Fan) or Full Irritability (Shi Fan), this formula is suitable to induce vomiting for resolution. Empty Irritability refers to symptoms such as inability to sleep due to irritability, tossing and turning, profound mental discomfort (Ao Nu), emptiness in the stomach, disturbance of hostile Qi in the diaphragm, softness upon pressing the epigastrium, dry tongue coating, inability to eat, absence of Chest Binding (Jie Xiong), and sweating only on the head. These are signs of Empty Irritability. Full Irritability refers to chest oppression and tying pain in the heart, which are signs of Full Irritability. This formula primarily vents heat from the diaphragm, allowing resolution through vomiting. It is unsuitable for those with pre-existing cold-damp patterns; hence, the classic warns against using it in patients with chronic loose stools.
Modern practitioners often stir-fry Zhizi until blackened, rendering it unable to induce vomiting. This original formula requires raw usage, which causes immediate vomiting upon ingestion. Xiangchi is steamed and possesses an ascending nature, thus carrying Zhizi to induce vomiting. It is a mild agent among emetic methods.
Whenever employing emetic methods, one must first assess the location of the pathogen. If there is fullness, hardness, and pain in the epigastrium, it is a Chest Binding syndrome, suitable for the Chest Binding resolving method. If there is epigastric stuffiness and hardness, it is Empty Stuffiness, suitable for the Heart-venting method. Here, since there is mental discomfort, tying pain in the heart, and softness in the epigastrium, emesis is indicated. A slight error can lead to significant deviation; careful differentiation is required.