飧泄，完谷不化也。脾胃气衰，不能熟腐水谷，而食物完出。经所谓脾病者，虚则腹满
肠鸣，飧泄不化是也。又清气在下，则生飧泄者，谓阳气虚则下陷也。又风气入脾，亦令飧泄。
夫风者木气也，而行于土中，风性善行，传化疾速，则熟腐不及，经所谓久风入中，为肠风
飧泄是也。又脾所生病，为胸满呕逆飧泄者，亦木气制土之所致也。又虚邪舍于肠胃，多寒
则肠鸣飧泄食不化者，土性喜温而恶寒，多寒则变化无权也。故飧泄之病，约有三端，一曰
虚，二曰风，三曰冷，而皆以虚为本也，亦曰虚泄。
胃风汤 治风冷虚气，入客肠胃，水谷不化，泄泻注下，腹胁虚满，肠鸣 痛。
人参 茯苓 川芎 官桂 当归 白芍 白术（各等分）
每服二钱，水一大盏，粟米百余粒，同煎七分去渣，稍热空心服。若虚劳嗽，加五味子
；若
防风芍药汤 治飧泄脉弦，身热腹痛而渴。
防风 芍药（各二钱） 黄芩（一钱） 苍术（三钱）
水煎服。此治风入脾之法也。
鞠 丸（方见濡泄。）
吴茱萸散（方见肠痹。）
升阳除湿汤 治胃气不升，清气在下，飧泄不已。
苍术（一钱半） 柴胡 升麻 羌活 防风 泽泻 猪苓 神曲（各七分） 麦芽 陈皮（
各五分） 甘草（三分，炙）
水二盏，煎一盏，去滓，空心服。如胃寒肠鸣，加益智仁、半夏（各五分），姜枣同煎。
《灵枢》云∶头有疾，取之足，谓阳病在阴也。足有疾，取之上，谓阴病在阳也。中有
疾，
傍取之，中者脾胃也，傍者少阳甲胆也。脾胃有疾，取之足少阳甲胆也。甲风木也，东方春
也。胃中真气者，谷气也。饮食不化，谷气下流者，湿胜故也。故曰，湿多成五泄，宜助甲
胆风以克之。又是升阳助清气上行之法也。大抵此症，本胃弱不能克化，夺食少食，欲使胃
气不困也。若药剂大，则胃不胜药，泄亦不止，当渐渐与之，不可多服饵也。
经云∶飧泄取三阴。三阴者，太阴也。宜补中益气汤去当归，加白芍。东垣云∶清气在
下者
，乃人之脾胃气衰，不能升发阳气，故用升麻、柴胡，助甘辛之味，以引元气之升，不令下
陷为飧泄也。
加味四君子汤 治气虚泄泻。
四君子加肉豆蔻（煨） 诃子（泡，各一钱） 姜枣煎。一方加缩砂、藿香、炮姜各五分，
山药、莲子、陈皮各一钱，乌梅一个，名参苓莲术散。
飧泄（完谷不化的泄泻），是指大便中含有未消化的食物。这是因为脾胃之气衰弱，不能将水谷充分腐熟消化，导致食物原样排出。《内经》所说脾脏患病时，虚证会出现腹部胀满、肠鸣音亢进以及完谷不化的飧泄，指的就是这种情况。另外，《内经》说“清气在下，则生飧泄”，意思是阳气虚弱就会下陷。还有风气侵入脾脏，也会导致飧泄。风属于木气，运行于土（脾）中，风性善于游走，传导变化迅速，使得食物来不及被完全腐熟消化，《内经》所谓“久风入中，为肠风飧泄”就是说的这种情况。此外，脾所生的疾病包括胸满、呕吐逆气、飧泄等，这也是木气克制土气所致。还有虚邪停留在肠胃，如果寒气多，就会出现肠鸣、飧泄、食物不化，这是因为土性喜欢温暖而厌恶寒冷，寒气过多则运化功能丧失权力。所以飧泄这种疾病，大约分为三个方面：一是虚，二是风，三是冷，但都以虚为本，所以也称为虚泄。
胃风汤：治疗风冷虚气客居肠胃，导致水谷不化，泄泻急迫如注，腹胁部感觉空虚胀满，肠鸣且疼痛。
组成：人参、茯苓、川芎、官桂、当归、白芍、白术（各等分）。
用法：每次服用二钱，加水一大盏，粟米百余粒，共同煎煮至七分，去渣滓，趁稍热时在空腹时服用。如果有虚劳咳嗽，加五味子；
防风芍药汤：治疗脉象弦、身体发热、腹痛且口渴的飧泄。
组成：防风、芍药（各二钱）、黄芩（一钱）、苍术（三钱）。
用法：水煎服。这是治疗风邪侵入脾脏的方法。
升阳除湿汤：治疗胃气不升，清气在下，导致飧泄不止。
组成：苍术（一钱半）、柴胡、升麻、羌活、防风、泽泻、猪苓、神曲（各七分）、麦芽、陈皮（各五分）、甘草（三分，炙）。
用法：加水两盏，煎煮至一盏，去渣滓，空腹服用。如果伴有胃寒肠鸣，加益智仁、半夏（各五分），加生姜、大枣同煎。
《灵枢》说：“头部有病，取足部的穴位治疗”，这是指阳病在阴经；“足部有病，取上部的穴位治疗”，这是指阴病在阳经。体内有病，取旁侧的穴位治疗，这里的“中”指脾胃，“傍”指少阳胆经。脾胃有疾病，取足少阳胆经的穴位治疗。胆属甲木，对应东方春季。胃中的真气，即谷气。饮食不化，谷气下流，是因为湿气胜的缘故。所以说，“湿气多会导致五种泄泻”，应当助长甲胆的风木之气来克制它。这也是升发阳气、帮助清气上升的方法。大抵这类病症，根本原因是胃弱不能消化，应当减少饮食或少食，以使胃气不被困阻。如果药量过大，胃无法承受药物，泄泻也不会停止，应当逐渐给药，不可大量服用。
《内经》说：“飧泄取三阴经”。三阴经，指的是太阴经。适宜使用补中益气汤去掉当归，加入白芍。李东垣说：“清气在下”，是由于人的脾胃气衰，不能升发阳气，所以使用升麻、柴胡，辅助甘辛味的药物，以引导元气上升，不让其下陷成为飧泄。
加味四君子汤：治疗气虚引起的泄泻。
组成：四君子汤加上煨肉豆蔻、泡诃子（各一钱），加生姜、大枣煎服。另一方案加入缩砂、藿香、炮姜各五分，山药、莲子、陈皮各一钱，乌梅一个，名为参苓莲术散。
Sunchang diarrhea (diarrhea with undigested food) refers to the passage of stool containing uncooked food. This occurs because the Qi of the Spleen and Stomach is deficient, failing to adequately decompose and transform water and grain, resulting in food being excreted intact. As stated in the Classics regarding diseases of the Spleen, deficiency syndromes manifest as abdominal fullness, borborygmus, and Sunchang diarrhea with undigested food. Furthermore, "when clear Yang fails to ascend and remains below, Sunchang diarrhea arises," meaning that when Yang Qi is deficient, it sinks downward. Additionally, Wind pathogen invading the Spleen can also cause Sunchang diarrhea. Wind belongs to Wood Qi and moves within Earth (the Spleen); since Wind has a nature of rapid movement and transmission, transformation occurs too quickly for food to be fully decomposed. The Classics state, "Long-standing Wind entering the interior causes Intestinal Wind and Sunchang diarrhea." Moreover, diseases generated by the Spleen include chest fullness, vomiting and rebellious Qi, and Sunchang diarrhea, which are caused by Wood Qi overacting on Earth. Also, when Empty Pathogens reside in the intestines and stomach, excessive Cold leads to borborygmus, Sunchang diarrhea, and indigestion, because Earth favors warmth and dislikes Cold; excessive Cold renders the transformative power ineffective. Therefore, Sunchang diarrhea can be categorized into three aspects: one is Deficiency, two is Wind, and three is Cold, but all are rooted in Deficiency, hence also called Deficient Diarrhea.
Weifeng Tang (Stomach Wind Decoction): Treats Wind-Cold and Deficient Qi lodging in the intestines and stomach, causing failure to digest water and grain, urgent watery diarrhea, empty fullness in the abdomen and hypochondrium, and painful borborygmus.
Ingredients: Renshen (Ginseng Radix), Fuling (Poria), Chuanxiong (Ligusticum Rhizome), Guigui (Cinnamon Twig), Danggui (Angelicae Sinensis Radix), Baishao (White Peony Root), Baizhu (Atractylodis Rhizoma) (equal parts).
Administration: Take 2 qian per dose, add one large cup of water and over 100 grains of millet, decoct together until reduced to 7/10 volume, strain, and drink slightly warm on an empty stomach. If accompanied by deficiency consumptive cough, add Wuweizi (Schisandrae Fructus).
Fangfeng Shaoyao Tang (Saposhnikovia and Peony Decoction): Treats Sunchang diarrhea with a wiry pulse, fever, abdominal pain, and thirst.
Ingredients: Fangfeng (Saposhnikoviae Radix), Shaoyao (Peony Root) (each 2 qian), Huangqin (Scutellariae Radix) (1 qian), Cangzhu (Atractylodis Rhizoma) (3 qian).
Administration: Decoct in water and take orally. This is a method for treating Wind invading the Spleen.
Ju Wan (Chrysanthemum Pill) (Formula see under Runxie).
Wuzhuyu San (Evodia Powder) (Formula see under Changbi).
Shengyang Chishi Tang (Raise Yang and Dampness-Draining Decoction): Treats failure of Stomach Qi to ascend, clear Yang remaining below, leading to persistent Sunchang diarrhea.
Ingredients: Cangzhu (Atractylodis Rhizoma) (1.5 qian), Chaihu (Bupleuri Radix), Shengma (Cimicifugae Rhizoma), Qianghuo (Notopterygii Rhizoma et Radix), Fangfeng (Saposhnikoviae Radix), Zexie (Alismatis Rhizoma), Zhuling (Polyporus), Shenqu (Massa Medicata Fermentata) (each 0.7 qian), Maiya (Hordei Fructus Germinatus), Chenpi (Citri Reticulatae Pericarpium) (each 0.5 qian), Gancao (Glycyrrhizae Radix et Rhizoma) (0.3 qian, honey-fried).
Administration: Add two cups of water, decoct to one cup, strain, and take on an empty stomach. If accompanied by Stomach Cold and borborygmus, add Yizhiren (Alpinia Oxyphylla Fructus) and Banxia (Pinelliae Rhizoma) (each 0.5 qian), decoct with Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus).
The *Lingshu* states: "Diseases of the head are treated by points on the feet," referring to Yang diseases affecting Yin meridians; "Diseases of the feet are treated by points above," referring to Yin diseases affecting Yang meridians. Diseases within the center are treated by points on the sides; "Center" refers to the Spleen and Stomach, and "Side" refers to the Shaoyang Gallbladder meridian. For diseases of the Spleen and Stomach, points on the Foot-Shaoyang Gallbladder meridian should be selected. Jia (Yang) represents Wood, corresponding to the East and Spring. The true Qi in the Stomach is Grain Qi. When food is not digested and Grain Qi flows downward, it is due to excess Dampness. Thus, it is said, "Excess Dampness leads to the five types of diarrhea"; one should assist the Wind-Wood of the Jia-Gallbladder to overcome it. This is also a method of raising Yang and assisting the ascent of Clear Yang. Generally, this condition stems from weak Stomach function unable to digest; reducing food intake or eating less prevents the Stomach Qi from being constrained. If the medicinal dosage is too large, the Stomach cannot tolerate the medicine, and diarrhea will not cease; medication should be administered gradually, avoiding large doses.
The Classics state: "For Sunchang diarrhea, select the Three Yin meridians." The Three Yin refers to the Taiyin meridian. It is appropriate to use Buzhong Yiqi Tang (Tonify the Middle and Augment the Qi Decoction) removing Danggui (Angelicae Sinensis Radix) and adding Baishao (White Peony Root). Li Dongyuan stated: "Clear Yang remaining below" results from the deficiency of Spleen and Stomach Qi, which fails to raise Yang Qi. Therefore, Shengma (Cimicifugae Rhizoma) and Chaihu (Bupleuri Radix) are used to assist sweet and acrid flavors to guide Yuan Qi upward, preventing it from sinking and causing Sunchang diarrhea.
Jiawei Sijunzi Tang (Modified Four Gentlemen Decoction): Treats diarrhea due to Qi deficiency.
Ingredients: Sijunzi Tang plus Rou Doukou (Myristicae Semen, roasted), Hezi (Terminalia Chebulae Fructus, soaked) (each 1 qian), decoct with Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus). Another prescription adds Suisha (Amomi Fructus Rotundus), Huoxiang (Agastaches Herba), Paojiang (Zingiberis Rhizoma Preparatum) (each 0.5 qian), Shanyao (Dioscoreae Rhizoma), Lianzi (Nelumbinis Semen), Chenpi (Citri Reticulatae Pericarpium) (each 1 qian), and Wumei (Mume Fructus) (one piece), named Shenling Lianzhu San (Ginseng, Poria, Lotus Seed, and Atractylodes Powder).