泄泻之因多端。而要以脾胃为本。脾胃者土也。处于中州。浇灌四旁。清浊以分。水谷以别。皆藉此健运
之能。而升降开阖。由之布化。尚何沥泻之虞哉。惟中气稍弛。风胜则飧泻而完谷不化。寒胜则洞泻而澄澈清
冷。湿胜则濡泻而糟粕不实。热胜则火泻而暴注下迫。更有食积痰饮。则腹中或痛或不痛。反得泻而减也。大
瘕泻。则腹中有瘕。时作时止也。肾泻。则每于子后发。余时则安也。盖土旺则能制水。水旺亦足凌土。湿郁
则能成热。热郁亦足助湿。浊气则能侵上。清气亦足陷下。故治泻之法。不可一端而竟。扶脾正也。而有时乎
平胃。分利常也。而有时乎升提。温补当也。而有时乎清热。况于食积宜消。痰积宜降。瘕聚宜调。肾虚宜补。
且有面色黄白。似乎
脾虚。而补之不效者。以湿热之未清也。亦有久泻不止。习以为恒。而止之
反剧者。亦积热之不解也。苟执脾土喜温恶寒。喜燥恶湿之说。而概以温
热行之。知常而不知变。知经而不知权。使遇中虚且寒者。诚然得矣。倘或
蕴隆不解。不且益其邪而成痼疾也哉。至于治泻九法。士材言之详矣。余不及赘。
胃苓汤
苍术（米泔制） 浓朴（姜制） 陈皮（各一钱） 甘草（三分炙） 白术（八分土炒）
茯苓 泽泻（各一钱） 肉桂（三分） 猪苓（一钱）
加姜枣水煎。或分用合用皆可。
薷苓汤 治暑泻。
香薷 黄连（姜汁炒） 浓朴（姜制） 扁豆（炒） 猪苓
泽泻 白术（土炒） 茯苓（各一钱） 甘草（三分）
姜三片水煎。
四神丸 治脾肾两虚。饮食不思。子后泄泻。
肉果（面煨二两） 补骨脂（胡桃制四两） 五味子（二两） 吴茱萸（浸炒一两）
为末。生姜八两。红枣百枚。煮熟丸。
泄泻的成因多种多样。但关键在于以脾胃为本。脾胃属土，位居中焦（人体中部），灌溉滋养四周脏腑，分清泌浊，分别水谷精微与糟粕，都依赖于此健运的功能。气机的升降出入、开合变化，由此布散转化，哪里还会有泄泻的忧虑呢？只有当中间之气稍显松弛时，风邪偏胜则导致飧泄（大便中含有未消化的食物）且完谷不化；寒邪偏胜则导致洞泄（腹泻如水直下）且排泄物澄澈清冷；湿邪偏胜则导致濡泄（大便稀溏不成形）且糟粕不实；热邪偏胜则导致火泄（暴注下迫）且急迫难忍。更有食积和痰饮阻滞，则腹部有时疼痛有时不痛，反而在泻后减轻。大瘕泄，则是腹中有瘕聚（肿块），时作时止。肾泄，则多在子时（夜间11点至凌晨1点）之后发作，其余时间则安宁。这是因为土旺则能制水，水旺亦足以凌犯脾土；湿郁结则能化热，热郁结亦足以助长湿气；浊气上逆则能侵犯上部，清气下陷则导致下部病变。所以治疗泄泻的方法，不能拘泥于一种。扶正健脾是常法，但有时需要平胃燥湿；分利小便也是常法，但有时需要升提清气；温补阳气恰当，但有时需要清热。况且对于食积应当消导，痰积应当降逆，瘕聚应当调理，肾虚应当补益。并且有面色黄白，看似脾虚，但补益却无效的情况，这是因为湿热尚未清除。也有久泻不止，习以为常，而强行止泻反而加重的情况，这也是因为积热未解。如果固执于“脾土喜温恶寒，喜燥恶湿”的说法，而一概使用温热药物治疗，这是知常道而不知变通，知常规而不知权宜。如果遇到中气虚弱且兼寒的患者，确实有效。但如果体内蕴结之热不解，岂不是更加助长邪气从而形成顽固疾病吗？至于治疗泄泻的九种方法，士材（李中梓的字）已经讲得很详细了，我不再赘述。
胃苓汤
苍术（用米泔水制） 厚朴（用姜汁制） 陈皮（各一钱） 甘草（三分，炙） 白术（八分，土炒）
茯苓 泽泻（各一钱） 肉桂（三分） 猪苓（一钱）
加入生姜、大枣，用水煎煮。可以分开服用也可以合并服用皆可。
薷苓汤 治疗暑湿泄泻。
香薷 黄连（用姜汁炒） 厚朴（用姜汁制） 扁豆（炒） 猪苓
泽泻 白术（土炒） 茯苓（各一钱） 甘草（三分）
生姜三片，用水煎煮。
四神丸 治疗脾肾两虚，饮食不思，子后泄泻。
肉豆蔻（面煨二两） 补骨脂（胡桃仁制四两） 五味子（二两） 吴茱萸（浸泡后炒一两）
研为细末。生姜八两，红枣一百枚，煮熟后捣烂制成丸剂。
The causes of diarrhea are diverse. However, the key lies in taking the Spleen and Stomach as the root. The Spleen and Stomach belong to Earth, located in the Middle Jiao (the central region of the body), irrigating and nourishing the surrounding organs, separating the clear from the turbid, and distinguishing between water/grain essence and waste. All of this relies on their vigorous transportation and transformation function. Through the ascending and descending movements, as well as opening and closing mechanisms, Qi is distributed and transformed; thus, where would there be any worry of diarrhea? Only when the Central Qi becomes slightly lax does specific pathogenic factors lead to distinct types: if Wind is excessive, it leads to Sundiarrhea (diarrhea containing undigested food) with complete undigested grains passing through; if Cold is excessive, it leads to Dongdiarrhea (profuse watery diarrhea) with clear and cold excrement; if Dampness is excessive, it leads to Rudiarrhea (loose, unformed stools) with incomplete waste; if Heat is excessive, it leads to Huodiarrhea (violent sudden diarrhea with urgency) with pressing downward sensations. Furthermore, Food Stagnation and Phlegm-Fluid retention may cause abdominal pain that is either present or absent, which actually alleviates after defecation. Da Jia Xie (Great Mass Diarrhea) involves masses in the abdomen that appear and disappear intermittently. Kidney Xie (Kidney Diarrhea) occurs mainly after Zi hour (11 PM to 1 AM), while remaining calm at other times. This is because when Earth is prosperous, it can control Water; when Water is prosperous, it can overwhelm Earth. When Dampness stagnates, it can generate Heat; when Heat stagnates, it can assist Dampness. Turbid Qi can invade upwards, while Clear Qi can sink downwards. Therefore, the methods for treating diarrhea cannot be limited to a single approach. Supporting the Spleen and rectifying righteousness is the standard method, but sometimes one must level the Stomach and dry dampness. Separating and draining via urination is also standard, but sometimes one must lift and raise the Clear Qi. Warming and tonifying is appropriate, but sometimes one must clear Heat. Moreover, for Food Stagnation, one should eliminate it; for Phlegm Stagnation, one should descend it; for Mass Aggregation, one should regulate it; for Kidney Deficiency, one should tonify it. There are cases where the complexion is yellowish-white, appearing as Spleen Deficiency, yet tonification yields no effect because Damp-Heat has not been cleared. There are also cases of chronic diarrhea persisting for a long time, becoming habitual, where stopping it abruptly makes it worse because accumulated Heat has not been resolved. If one adheres rigidly to the theory that "Earth of the Spleen prefers warmth and dislikes cold, prefers dryness and dislikes dampness," and generally applies warm-hot treatments, this is knowing the constant but ignoring change, knowing the canon but ignoring expediency. For patients with Middle Deficiency and Cold, this may indeed be effective. However, if internal accumulated Heat remains unresolved, will it not further exacerbate the pathogen and become an intractable disease? As for the nine methods of treating diarrhea, Shicai (Li Zhongzi's courtesy name) has explained them in detail; I will not add more.
Weiling Tang (Stomach-Ling Decoction)
Cangzhu (Atractylodis Rhizoma, processed with rice wash water) Houpo (Magnoliae Officinalis Cortex, processed with ginger juice) Chenpi (Citri Reticulatae Pericarpium, each 1 qian) Gancao (Glycyrrhizae Radix et Rhizoma, 3 fen, honey-fried) Baizhu (Atractylodis Macrocephalae Rhizoma, 8 fen, soil-fried)
Fuling (Poria) Zexie (Alismatis Rhizoma, each 1 qian) Rougui (Cinnamomi Cortex, 3 fen) Zhuling (Polyporus, 1 qian)
Add Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus), decoct with water. Can be taken separately or combined.
Ruling Tang (Artemisiae Argyi-Poria Decoction) Treats Summerheat-Damp Diarrhea.
Xiangru (Elsholtziae Herba) Huanglian (Coptidis Rhizoma, stir-fried with ginger juice) Houpo (Magnoliae Officinalis Cortex, processed with ginger juice) BianDou (Dolichoris Semen, stir-fried) Zhuling (Polyporus)
Zexie (Alismatis Rhizoma) Baizhu (Atractylodis Macrocephalae Rhizoma, soil-fried) Fuling (Poria, each 1 qian) Gancao (Glycyrrhizae Radix et Rhizoma, 3 fen)
Decoct with three slices of Shengjiang (Zingiberis Rhizoma Recens).
Sishen Wan (Four Spirits Pill) Treats Spleen-Kidney Dual Deficiency, lack of appetite, and post-Zi hour diarrhea.
Rou Doukou (Myristicae Semen, baked in flour for two liang) Buguzhi (Psoraleae Fructus, processed with walnut kernels for four liang) Wuweizi (Schisandrae Fructus, two liang) Wuzhuyu (Evodiae Fructus, soaked and stir-fried for one liang)
Grind into fine powder. Use eight liang of Shengjiang (Zingiberis Rhizoma Recens) and one hundred Dazao (Jujubae Fructus), cook until soft, mash, and form pills.