病发于阴而反下之，为痞。（发热恶寒，为发于阳，误下则为结胸；无热恶寒，为发于阴，误
下则为痞气。）
伤寒下之后，若发热汗出者，为欲解；若心下满而硬痛者，此为结胸也；但满而不痛，此为痞
气，宜半夏泻心汤。
甘草 黄芩 干姜 人参（各一两半） 黄连（半两） 大枣（六枚） 半夏（一两一分）
咀，水六升，煮取三升，去滓，再煎一升半，温温饮一盏，日三夜二。（设下后津液入里，
胃虚上逆，寒结在心下，故宜辛甘发散。半夏下气，苦能去湿，兼通心气；又甘草力大，故干姜黄
连不能相恶也。）
心下痞，按之濡，其脉关上浮者，宜大黄黄连泻心汤。
大黄（一两） 黄连 黄芩（各半两）
咀，以虾眼沸汤一升渍之，须臾绞去滓，温温分四服，得利止后服。（寒湿迫心气不行，欲
作热也。）
心下痞闷，而复恶寒汗出者，大黄黄连泻心汤内加附子主之。
附子（一枚，炮去皮尖，四破，以水三合，煎一合。去附子，以附子汁内汤中，和匀服之。）
与泻心汤而痞不解，其人渴而口干燥，小便不利者，五苓散主之。（方在可水证中。）
伤寒汗出，解之后，胃中不和，心下痞硬，干噫食臭，胁下有水气，腹中雷鸣，下利，宜生
姜泻心汤。
生姜（二两） 人参 甘草 黄芩（各一两半） 半夏（一两一分） 大枣（六枚） 黄连 干
姜（各半两）
咀，水五升，煮取三升，去滓，再煎取一升半，温作四服。（胃中不和，为少阳木气所制，
故用二姜之辛味。）
伤寒中风，医反下之，其人下利日数十行，谷不化，腹中雷鸣，心下痞硬而满，干呕心烦不得
安。医见心下痞，谓病不尽，复下之，其痞益甚，此非结热，但以胃中
虚，客气上逆，故使硬也，甘草泻心汤主之。
甘草（二两） 黄芩 干姜 人参（各半两） 半夏（一两一分） 大枣（六枚） 黄连（半两）
咀，水五升，煎至三升，去滓，再煎取一升半，温作四服。（胃虚故加甘味。）
大下后，复发汗，心下痞，恶寒者，表未解，不可攻痞，当先解表，表解乃可攻痞。攻痞宜大
黄黄连泻心汤。（前加附子，是汗出多而恶寒，表将解而里结未除故也；此证是发汗后无汗恶寒，故
先须解表也。）
伤寒发热，汗出不解，心下痞硬，呕吐下利者，大柴胡汤主之。（汗出，呕吐下利，是胃中津液
燥，里有结实，非胃虚也，故以大柴胡汤下之。）
病患胁下素有痞，连脐旁，痛引小腹入阴筋者，此为脏结，死。
疾病发于阴证却误用攻下法，会导致痞证。（发热恶寒，属于发于阳证，误用攻下则形成结胸；无热恶寒，属于发于阴证，误用攻下则形成痞气。）
伤寒经过攻下治疗后，如果出现发热、汗出的症状，说明病邪将要解除；如果感到心下部胀满且坚硬疼痛，这是结胸证；如果只是胀满而不疼痛，这是痞气证，适宜使用半夏泻心汤。
方药组成：甘草、黄芩、干姜、人参（各一两半），黄连（半两），大枣（六枚），半夏（一两一分）。
将药材切碎，加水六升，煎煮至三升，滤去药渣，再次煎煮至一升半，温热服用一盏，白天服三次，夜间服两次。（如果在攻下后津液内陷，导致胃虚气逆，寒邪凝结在心下部，因此适宜用辛甘发散之法。半夏能降气，苦味能祛湿并兼通心气；又因甘草药力宏大，所以干姜与黄连不会产生相恶的副作用。）
心下部痞塞，按压时柔软，脉象在关部呈现浮象的，适宜使用大黄黄连泻心汤。
方药组成：大黄（一两），黄连、黄芩（各半两）。
将药材切碎，用刚沸腾的一升水浸泡片刻，随即绞去药渣，温热分四次服用，一旦大便通畅即停止后续服药。（寒湿逼迫心气运行不畅，欲转化为热邪。）
心下部痞闷，同时伴有恶寒、汗出的，在大黄黄连泻心汤中加入附子主治。
附子（一枚，炮制去皮尖，切成四块，用水三合煎煮出一合。取出附子，将附子汁加入药汤中，混合均匀后服用。）
服用泻心汤后痞证未解，患者口渴、口唇干燥，小便不利的，适宜使用五苓散主治。（该方剂记载在“可水证”章节中。）
伤寒汗出表解之后，胃中不和，心下部痞塞坚硬，嗳气带有食物腐臭味，胁下有积水之气，肠鸣音如雷，腹泻的，适宜使用生姜泻心汤。
方药组成：生姜（二两），人参、甘草、黄芩（各一两半），半夏（一两一分），大枣（六枚），黄连、干姜（各半两）。
将药材切碎，加水五升，煎煮至三升，滤去药渣，再次煎煮至一升半，温热分四次服用。（胃中不和，是因为受到少阳木气的制约，所以使用两种姜的辛味来调理。）
伤寒或中风，医生误用攻下法，导致患者每天腹泻数十次，完谷不化，肠鸣音如雷，心下部痞塞坚硬且胀满，干呕，心烦不安。医生看到心下部痞塞，认为病邪未尽，再次使用攻下法，结果痞证更加严重。这并非实热结聚，而是因为胃气虚弱，客气上逆，从而导致痞硬，适宜使用甘草泻心汤主治。
方药组成：甘草（二两），黄芩、干姜、人参（各半两），半夏（一两一分），大枣（六枚），黄连（半两）。
将药材切碎，加水五升，煎煮至三升，滤去药渣，再次煎煮至一升半，温热分四次服用。（因为胃气虚弱，所以增加甘味药物以补益。）
在剧烈攻下后，又再次发汗，出现心下部痞塞，伴有恶寒的，说明表证尚未解除，不可直接攻治痞证，应当先解除表证，待表证解除后再攻治痞证。攻治痞证适宜使用大黄黄连泻心汤。（此前加附子的情况，是汗出过多而恶寒，表证即将解除但里结未除；此证是发汗后无汗且恶寒，所以必须先解表。）
伤寒发热，汗出后病不解，心下部痞塞坚硬，伴有呕吐、腹泻的，适宜使用大柴胡汤主治。（汗出、呕吐、腹泻，说明胃中津液干燥，里有结实，并非胃虚，所以用大柴胡汤攻下。）
Diseases originating from Yin syndromes, if mistakenly treated with purgation, result in Pi syndrome (a sensation of fullness and obstruction in the epigastrium). (Fever and aversion to cold indicate origin from Yang syndromes; mistaken purgation leads to Jie Xiong syndrome [chest binding]; absence of fever with aversion to cold indicates origin from Yin syndromes; mistaken purgation leads to Pi Qi [epigastric fullness].)
After purgation for Taiyang Cold Damage (Shanghan), if fever and sweating occur, it indicates the disease is about to resolve. If there is fullness and hardness with pain in the epigastrium, this is Jie Xiong syndrome. If there is only fullness without pain, this is Pi Qi, and Banxia Xiexin Tang (Pinellia Decoction to Drain the Epigastrium) is indicated.
Ingredients: Gancao (Radix Glycyrrhizae Preparata), Huangqin (Radix Scutellariae), Ganjiang (Rhizoma Zingiberis Preparatum), Renshen (Radix Ginseng) (each 1.5 liang); Huanglian (Rhizoma Coptidis) (0.5 liang); Dazao (Fructus Jujubae) (6 pieces); Banxia (Rhizoma Pinelliae Preparatum) (1.1 liang).
Crush the herbs, add six sheng of water, boil to obtain three sheng, remove the dregs, and decoct again to obtain one and a half sheng. Drink one cup warm, three times during the day and twice at night. (If after purgation fluids enter the interior, causing stomach deficiency and rebellious qi, with cold knotting in the epigastrium, acrid-sweet dispersing methods are suitable. Banxia directs qi downward; bitter flavors eliminate dampness and unblock Heart qi; furthermore, Gancao has strong potency, so Ganjiang and Huanglian do not mutually antagonize each other.)
For epigastric Pi with softness upon palpation and a floating pulse at the Guan position, Dahuang Huanglian Xiexin Tang (Rhubarb and Coptis Decoction to Drain the Epigastrium) is indicated.
Ingredients: Dahuang (Radix et Rhizoma Rhei) (1 liang); Huanglian, Huangqin (each 0.5 liang).
Crush the herbs, steep in one sheng of boiling water ("shrimp-eye" boiling point) for a moment, then strain and remove dregs. Drink warm, divided into four doses. Stop subsequent doses once bowel movement occurs. (Cold-dampness forces Heart qi to stagnate, intending to transform into heat.)
For epigastric Pi accompanied by aversion to cold and sweating, Fuzi (Radix Aconiti Lateralis Preparata) should be added to Dahuang Huanglian Xiexin Tang.
Fuzi (one piece, processed, skin and tips removed, cut into four pieces, decocted in three he of water to obtain one he. Remove the Fuzi, add the Fuzi juice to the herbal decoction, mix well, and take.)
If Pi does not resolve after taking Xiexin Tang, and the patient experiences thirst, dry mouth, and dysuria, Wuling San (Five-Ingredient Powder with Poria) is indicated. (The formula is recorded in the "Water-Accessible Syndromes" section.)
After Taiyang Cold Damage resolves via sweating, if there is disharmony in the Stomach, hard epigastric Pi, belching with food odor, fluid accumulation under the hypochondrium, borborygmus, and diarrhea, Shengjiang Xiexin Tang (Fresh Ginger Decoction to Drain the Epigastrium) is indicated.
Ingredients: Shengjiang (Rhizoma Zingiberis Recens) (2 liang); Renshen, Gancao, Huangqin (each 1.5 liang); Banxia (1.1 liang); Dazao (6 pieces); Huanglian, Ganjiang (each 0.5 liang).
Crush the herbs, add five sheng of water, boil to obtain three sheng, remove dregs, and decoct again to obtain one and a half sheng. Drink warm, divided into four doses. (Disharmony in the Stomach is constrained by Shaoyang Wood qi, hence the use of the acrid flavor of both types of ginger.)
In Taiyang Cold Damage or Wind Strike, if the physician mistakenly uses purgation, resulting in frequent diarrhea (dozens of times daily), undigested food, borborygmus, hard and full epigastric Pi, dry retching, irritability, and restlessness. Seeing the epigastric Pi, the physician assumes residual pathogenic factors and purges again, worsening the Pi. This is not excess heat knotting, but rather Stomach deficiency with rebellious guest qi, causing hardness. Gancao Xiexin Tang (Licorice Decoction to Drain the Epigastrium) is indicated.
Ingredients: Gancao (2 liang); Huangqin, Ganjiang, Renshen (each 0.5 liang); Banxia (1.1 liang); Dazao (6 pieces); Huanglian (0.5 liang).
Crush the herbs, add five sheng of water, boil to three sheng, remove dregs, and decoct again to obtain one and a half sheng. Drink warm, divided into four doses. (Because of Stomach deficiency, sweet flavors are increased.)
After severe purgation followed by sweating, if epigastric Pi and aversion to cold occur, the exterior syndrome remains unresolved. One must not attack the Pi directly; first resolve the exterior, then treat the Pi. To treat the Pi, Dahuang Huanglian Xiexin Tang is indicated. (The previous addition of Fuzi was for cases with excessive sweating and aversion to cold, where the exterior was resolving but interior knotting remained; this case involves no sweating and aversion to cold after sweating, so exterior resolution is required first.)
In Taiyang Cold Damage with fever, unresolved sweating, hard epigastric Pi, vomiting, and diarrhea, Da Chaihu Tang (Major Bupleurum Decoction) is indicated. (Sweating, vomiting, and diarrhea indicate dryness of Stomach fluids and interior excess knotting, not Stomach deficiency; thus, Da Chaihu Tang is used to purge.)
If a patient has a chronic Pi mass under the hypochondrium extending to the umbilicus, with pain radiating to the lower abdomen and genital tendons, this is Zang Jie (Visceral Binding), which is fatal.