治食已即吐者。此汤主之。
大黄（四两。） 甘草（二两。）
上二味。以水三升。煮取一升。分温再服。
歌曰 食方未久吐相随。（食已即吐。）两热冲来自不支。（胃素有热。食复入之。两热
相冲。不停片刻而吐出。）四两大黄二两草。上从下取法神奇。
蔚按。师云。欲吐者不可下之。又云。食已即吐者。大黄甘草汤下之。二说相反。何也。
曰。病在上而欲吐。宜因而越之。若逆之使下。则愦乱矣。若既吐矣。吐而不已。是有升
无
尤在泾云。云雾出于地。而雨露降于天。地不承则天不降矣。可见天地阴阳同此气机。
和则
多及
呕吐
治胃反。吐而渴欲饮水者。此汤主之。
茯苓（半斤。） 泽泻（四两。） 甘草 桂枝（各二两。） 白术（三两。） 生姜（四
两。）
上六味。以水一斗。煮取三升。内泽泻。再煮。取二升半。温服八合。日三服。 外台。
治消
歌曰 吐方未已渴频加。（与吐后渴为欲愈者不同。亦与猪苓散症未吐而先渴者不同。）
苓
水。
徐忠可云。此方于五苓散中去猪苓者。以胃反证水从吐出。中无水气而渴也。加生姜、
甘草
治吐后渴欲得水而贪饮者。此汤主之。兼主微风脉紧头痛。
文蛤 石膏（各五两。） 麻黄 甘草 生姜（各三两。） 杏仁（五十粒。） 大枣
（十二枚
上七味。以水六升。煮取二升。温服一升。汗出即愈。
歌曰 吐而贪饮证宜详。文蛤石膏五两量。十二枣枚杏五十。麻甘三两等生姜。
元犀按。水虽随吐而去。而热不与水俱去。故贪饮不休。与思水者不同。方中麻黄与石
膏并
主微
治疗进食后立即呕吐的患者，用此方主治。
大黄（四两） 甘草（二两）
以上两味药，用水三升，煎煮至一升，分两次温服。
歌诀云：食物刚吃下不久就随之呕吐。（即食已即吐。）两种热邪冲撞导致身体难以支撑。（胃中原本有热，食物再次进入，两种热邪相冲，不停留片刻便吐出。）四两大黄配二两甘草，采用上病下治的方法效果神奇。
蔚按：老师曾说，想要呕吐的病人不可使用泻下法；又说，进食后立即呕吐的病人，应用大黄甘草汤泻下。这两种说法看似相反，为什么呢？
回答说：病位在上部且想要呕吐的，应当顺应其势使其向上排出；如果强行逆其势使其向下，就会造成混乱。如果已经呕吐了，但呕吐不止，这是只有上升没有下降（的气机）。
尤在泾说：云雾从地面升起，而雨露从天降落。地面不能承接则天空无法降雨。可见天地阴阳之气机是相同的。
调和则……
多涉及……
呕吐
治疗胃反证，呕吐且口渴想喝水的患者，用此方主治。
茯苓（半斤） 泽泻（四两） 甘草 桂枝（各二两） 白术（三两） 生姜（四两）
以上六味药，用水一斗，煎煮至三升，加入泽泻，再煎煮，取二升半，每次温服八合，每日三次服用。《外台秘要》记载，治疗消渴……
歌诀云：呕吐尚未停止口渴又加重。（这与呕吐后口渴表示将要痊愈的情况不同，也与猪苓散证中未呕吐先出现口渴的情况不同。）
茯苓……
水。
徐忠可说：此方在五苓散中去掉猪苓的原因，是因为胃反证的水气随呕吐而出，中焦没有水气滞留所以感到口渴。加入生姜、甘草……
治疗呕吐后口渴想喝水且贪饮不止的患者，用此方主治。兼治轻微风邪、脉紧、头痛。
文蛤 石膏（各五两） 麻黄 甘草 生姜（各三两） 杏仁（五十粒） 大枣（十二枚）
以上七味药，用水六升，煎煮至二升，每次温服一升，出汗后即愈。
歌诀云：呕吐后贪饮的症状需要仔细辨析。文蛤和石膏各用五两量。十二枚大枣和五十粒杏仁。麻黄、甘草各三两，生姜也是三两。
元犀按：水液虽然随着呕吐排出了，但热邪并没有随水液一起去除，所以贪饮不止。这与思水（只想喝水但不一定大量饮用）的情况不同。方中麻黄与石膏并用……
主治轻微……
Treating patients who vomit immediately after eating, this decoction is the primary treatment.
Dahuang (Rhei Radix et Rhizoma) (4 liang) Gancao (Glycyrrhizae Radix et Rhizoma) (2 liang)
Take the above two ingredients, add three sheng of water, and boil to obtain one sheng. Divide into two doses and take warm.
The song states: Vomiting follows shortly after eating. (This refers to vomiting immediately after eating.) The clash of two types of heat overwhelms the body's resistance. (The stomach originally has internal heat; when food enters again, the two heats clash, causing immediate expulsion without retention.) Four liang of Dahuang paired with two liang of Gancao; the method of treating upper disorders by purging from below is miraculous.
Wei notes: The Master stated that for those wishing to vomit, purgatives should not be used. It is also stated that for those who vomit immediately after eating, Dahuang Gancao Tang should be used to purge. These two statements seem contradictory. Why?
It is said: When the pathology is in the upper jiao and there is a desire to vomit, one should follow the natural tendency to induce emesis. If one forces it downward against the trend, it will cause confusion and chaos. However, if vomiting has already occurred but continues incessantly, this indicates a mechanism where qi rises but does not descend.
You Zaijing said: Clouds and mist rise from the earth, while rain and dew descend from heaven. If the earth cannot receive them, heaven cannot send them down. This shows that the qi mechanism of yin and yang in heaven and earth is identical.
When harmonized...
Often involving...
Vomiting
Treating Wei Fan (Stomantic Reversal), characterized by vomiting and thirst with a desire to drink water, this decoction is the primary treatment.
Fuling (Poria) (8 liang) Zexie (Alismatis Rhizoma) (4 liang) Gancao (Glycyrrhizae Radix et Rhizoma) Guizhi (Cinnamomi Ramulus) (each 2 liang) Baizhu (Atractylodis Macrocephalae Rhizoma) (3 liang) Shengjiang (Zingiberis Rhizoma Recens) (4 liang)
Take the above six ingredients, add ten dou of water, and boil to obtain three sheng. Add Zexie, and boil again to obtain two and a half sheng. Take eight ge warm per dose, three times daily. *Waitai Mi Yao* records treating Xiao Ke (Wasting and Thirsting)...
The song states: Vomiting has not yet ceased, yet thirst intensifies. (This differs from thirst after vomiting which indicates recovery, and also differs from Zhu Ling San patterns where thirst precedes vomiting.)
Fuling...
Water.
Xu Zhongke said: The reason Puling (Polyporus) is removed from Wu Ling San in this formula is because in Wei Fan, the pathogenic water is expelled through vomiting; thus, there is no water qi stagnation in the middle jiao, leading to thirst. Adding Shengjiang and Gancao...
Treating patients who, after vomiting, feel thirsty, desire water, and drink greedily/excessively, this decoction is the primary treatment. It also treats mild wind pathogens, tight pulse, and headache.
Wen Ge (Arcae Concha) Shigao (Gypsum Fibrosum) (each 5 liang) Mahuang (Ephedrae Herba) Gancao (Glycyrrhizae Radix et Rhizoma) Shengjiang (Zingiberis Rhizoma Recens) (each 3 liang) Xingren (Prunus Armeniaca Seed) (50 grains) Dazao (Jujubae Fructus) (12 pieces)
Take the above seven ingredients, add six sheng of water, and boil to obtain two sheng. Take one sheng warm per dose. Recovery occurs upon sweating.
The song states: The symptom of greedy drinking after vomiting requires careful analysis. Wen Ge and Shigao are each used in five liang quantities. Twelve pieces of Dazao and fifty grains of Xingren. Mahuang and Gancao are each three liang, as is Shengjiang.
Yuan Xi notes: Although the fluids are lost through vomiting, the heat pathogen does not leave with the fluids; therefore, the craving for drinking persists. This differs from "Si Shui" (desiring water). In the formula, Mahuang and Shigao are used together...
Treating mild...