痘疮首尾皆忌泄泻，而后为尤甚，惟初热时，有随泄而随止者为吉。若自见黑点之后，
以致收靥，毒瓦斯俱已在表，俱要元气内充，大便坚实，庶能托载收成，若略泄泻，则中气虚弱，
变患百出矣。若初出之后而见
泄泻，则必难起难灌；既起之后而见泄泻，一泻则浆停，泻止则浆满；既灌之后而见泄泻，
则倒陷倒靥，内溃内败等证，无所不至，此实性命所关，最可畏也。今多见妄药误治，败人脾
气以致莫救者，犹云欲去其毒，泻泻无害，欺耶昧耶，庸莫甚矣。
凡治痘疹泄泻，只在辨其寒热，热者必湿滞之有余，寒者必元阳之不足。但十泻九虚而实
热者极少，故凡见泄泻、呕吐、腹痛而别无实热等证者，无论痘前痘后，俱速宜温救脾肾。此
大要也，当详察之，若失其真，误治则死。
一、虚寒泄泻，凡证无大热，口不喜冷，脉不洪数，腹无热胀，胸无烦躁，饮食减少而忽然
自利者，则悉属虚寒，切不可妄用寒凉之剂，再伤脾土，必致不救，宜温胃饮、养中煎、五君
子煎，或理中汤、四君子汤之类，随宜用之。若腹有微滞微胀而为泄泻者，宜六味异功煎，或
五味异功散加砂仁。若泄泻兼呕兼痛而气有不顺者，宜养中煎加丁香、木香，或四君子汤合二
仙散。若泄泻而山根、唇口微见青色，或口鼻微寒，手足不热，指尖微冷，泻色淡黄，或兼青白
，睡或露睛，此皆脾肾虚寒之证，非速救命门，终不见效，宜胃关煎、理阴煎主之，或陈氏十
二味异功散亦可。若泄泻势甚，用温脾之药不效者，则必用胃关煎，或理阴煎之类主之。若久泻
滑脱不能止者，宜胃关煎、温胃饮，或陈氏十二味异功散，送五德丸或肉豆蔻丸。若胃本不虚，
但以寒湿伤脾，或饮水而为泄泻者，宜佐关煎、抑扶煎，或益黄散加猪苓、泽泄，或五苓散俱佳。
一、蓄热泄泻，本不多见而间亦有之，然必有热证可据，方可用清利之药。如脉见洪数，
身有大热，口有大渴，喜冷恶热，烦躁多汗，或中满气粗，或痘色 肿红紫，或口鼻热赤，
小水涩痛之类，皆热证也。且热泻者必暴而甚，寒泄者必徐而缓，皆可辨之。然治热之法，当
察火之微甚，勿使药过于病，恐致伤脾，则必反为害。凡湿热内蓄，小水不利，微热不甚而为泄
泻者，宜五苓散、四苓散，或小厘清饮之类，加木通主之。若湿热稍甚，清浊不分而泄泻者，
宜四苓散加姜炒黄连，或合黄芩汤治之。若食多脉盛气壮而泄泻者，当从热治，宜黄芩汤加
黄连。若热在下焦，小水赤涩而泄泻者，宜大厘清饮，或合益元散。若湿热在脾，泄泻内热
而兼腹
痛者，宜香连丸。若颊赤身热，头痛咽疼，口疮烦躁而泄泻者，阳明火证也，宜泻黄散。若
湿热在脾，泻而兼呕者，黄芩汤加半夏、生姜，或《御药》大半夏汤加黄芩。若内热泄泻而兼气
虚者，四君子汤加芍药、黄连、木香。
一、发渴乃泄泻之常候，盖水泄于下，则津涸于上，故凡患泄泻者，必多口干口渴。但干
与渴不同，渴者欲饮，干者不欲饮，渴属阳而干属阴，此其辨也。然有渴欲饮水者，此火证也。
有渴欲饮汤者，此非火也。有虽欲饮水而不能多者，有口虽欲凉而胸腹畏寒者，此皆非火证也。
然则病渴者尚有阴阳之辨，而矧夫但干而不渴者，此实以水亏而然，若作火治，鲜不为害。故凡
有久泻津亡而作渴者，当审其非热而不可不壮其水也。
程氏曰∶泄泻须分寒热，寒者小便清，宜理中汤，或参苓白术散。然白术、茯苓非泄泻发
泡者不宜用，以其渗利故也。按此说可见治痘者，即渗利亦忌，顾可妄为消伐以残其气血津液乎？
陈氏曰∶凡泻频津耗则血气不荣，疮虽起发亦难收靥。如身温腹胀，气促切牙，烦躁谵妄
者皆难治，缘谷食去多，津液枯竭，故多死也，速宜与十一味木香散，或十二味异功散。
万氏曰∶疮未出而利者，邪并于里，实也，宜从清毒。疮已出而利者，邪达于表，里虚也，
宜治其虚。凡痘疮所忌，惟内虚泄泻，若温之固之而不愈者，此不治之证。
痘疮（天花）在病程的初期和后期都忌讳出现泄泻，而到了后期出现泄泻则更为严重。只有在初热阶段，如果泄泻随着发热消退而随即停止，这属于吉兆。如果在见到黑点之后，直到结痂收靥的过程中，毒邪之气都已经透发在体表，此时必须依靠体内元气的充盛和大便的坚实，才能托举毒邪并使其顺利收敛。如果稍有泄泻，就会导致中气虚弱，从而引发各种变证和祸患。如果在痘疹刚发出后就出现泄泻，那么痘疹必然难以起发和灌浆；如果痘疹已经起发后出现泄泻，一旦腹泻，痘浆就会停滞不前，腹泻停止后痘浆才会充盈；如果痘疹已经灌浆后出现泄泻，就会导致痘疹倒陷、结痂异常、内部溃烂败坏等证候，无所不至，这确实关系到性命，是最令人畏惧的。如今常见因乱用药物误治，损伤脾气而导致无法挽救的情况，这些人还声称想要通过泄泻来排出毒素，认为泄泻无害，真是欺骗且愚昧至极，庸医没有比这更严重的了。
凡是治疗痘疹引起的泄泻，关键在于辨别寒热属性。热证必然是湿滞有余的表现，寒证必然是元阳不足的表现。但是十次泄泻中有九次是虚证，实热证极少。因此，凡是见到泄泻、呕吐、腹痛而没有其他实热证候的，无论是在痘疹发出之前还是之后，都应迅速采用温补脾肾的方法进行救治。这是治疗的大要，应当详细考察，如果失去了真确的判断，误治就会导致死亡。
一、虚寒泄泻：凡是证候中没有大热，口不喜冷饮，脉象不洪大数急，腹部没有热胀感，胸部没有烦躁感，饮食减少而突然发生自发性下利的，都属于虚寒证。切不可妄用寒凉药剂，再次损伤脾土，否则必然导致无法挽救。适宜使用温胃饮、养中煎、五君子煎，或者理中汤、四君子汤之类，根据具体情况选用。如果腹部有轻微的阻滞和胀满而出现泄泻，适宜使用六味异功煎，或者五味异功散加砂仁。如果泄泻兼有呕吐和疼痛，且气机不畅，适宜使用养中煎加丁香、木香，或者四君子汤合二仙散。如果泄泻时山根（鼻根部）、唇口微微发青，或者口鼻微冷，手足不热，指尖微冷，大便颜色淡黄，或者兼带青色，睡眠时眼睛半睁露睛，这些都是脾肾虚寒的证候，如果不迅速急救命门之火，终究不会见效，适宜以胃关煎、理阴煎为主方，或者陈氏十二味异功散也可以。如果泄泻势头很猛，使用温补脾脏的药物无效，则必须使用胃关煎，或者理阴煎之类的主方。如果是久泻滑脱不禁无法止住的，适宜用胃关煎、温胃饮，或者陈氏十二味异功散，送服五德丸或肉豆蔻丸。如果胃气原本不虚，只是因为寒湿损伤脾脏，或者因为饮水过多而导致泄泻的，适宜使用佐关煎、抑扶煎，或者益黄散加猪苓、泽泻，或者五苓散，这些方剂都很佳效。
一、蓄热泄泻：本来不多见，但偶尔也有这种情况，然而必须有热证的依据，才可以清利湿热。例如脉象洪大数急，身体有大热，口中大渴，喜欢冷饮厌恶热物，烦躁多汗，或者胸中胀满气息粗重，或者痘色肿胀红紫，或者口鼻热赤，小便涩痛等，都属于热证。而且热性泄泻必定暴烈而严重，寒性泄泻必定缓慢而缓和，都可以据此辨别。然而治疗热证的方法，应当观察火邪的轻重，不要让药力超过病情，恐怕会损伤脾脏，那样反而会成为害处。凡是湿热内蕴，小便不利，轻微发热且不严重而导致的泄泻，适宜使用五苓散、四苓散，或者小厘清饮之类，加木通为主方。如果湿热稍重，清浊不分而导致的泄泻，适宜使用四苓散加姜炒黄连，或者合用黄芩汤治疗。如果饮食积滞多，脉象盛大气壮而导致的泄泻，应当从热证治疗，适宜使用黄芩汤加黄连。如果热邪在下焦，小便赤涩而导致的泄泻，适宜使用大厘清饮，或者合用益元散。如果湿热在脾脏，泄泻伴有内热且兼有腹痛的，适宜使用香连丸。如果脸颊发红身体发热，头痛咽痛，口舌生疮烦躁而泄泻的，这是阳明火证，适宜使用泻黄散。如果湿热在脾脏，泄泻兼有呕吐的，可用黄芩汤加半夏、生姜，或者《御药院方》中的大半夏汤加黄芩。如果内热泄泻兼有气虚的，可用四君子汤加芍药、黄连、木香。
一、口渴是泄泻的常见伴随症状，因为水液从下部泄出，上部津液就会枯竭，所以凡是患泄泻的人，大多会出现口干口渴。但是“干”与“渴”是不同的，“渴”是想喝水，“干”是不想喝水，“渴”属阳而“干”属阴，这是它们的区别所在。然而，有的想喝水，这是火证（热证）。有的想喝热汤，这不是火证。有的虽然想喝水但不能多喝，有的口虽想凉但胸腹怕冷，这些都不是火证。既然病渴还有阴阳的区别，何况只是口干而不渴的情况呢？这实际上是由于水亏（阴液不足）造成的，如果当作火证来治疗，很少有不造成危害的。所以凡是久泻导致津液亡失而作渴的，应当审察其非热证，不可不滋补其阴水。
程氏说：泄泻必须分寒热，寒证的小便清长，适宜用理中汤，或者参苓白术散。然而白术、茯苓对于泄泻伴有起泡者不宜使用，因为它们具有渗利的作用。按此说法可见，治疗痘疮的人，即使是渗利之法也忌讳使用，更何况可以妄用消伐之法来残害气血津液呢？
陈氏说：凡是腹泻频繁导致津液耗损，则血气不能荣养，痘疮即使起发也难以收靥。如果出现身体温和但腹胀，气促咬牙，烦躁谵语妄言的，都难治，因为谷食排泄过多，津液枯竭，所以大多死亡，应迅速给予十一味木香散，或者十二味异功散。
万氏说：痘疮未发出而腹泻的，是邪气并入于里，属实证，适宜从清解毒邪方面治疗。痘疮已发出而腹泻的，是邪气达于表，里气虚，适宜治疗其虚证。凡是痘疮所忌讳的，只有内虚泄泻，如果用温补固涩的方法而不能痊愈的，这是不治之证。
Chickpox (Smallpox) is contraindicated with diarrhea throughout the course of the disease, and it is particularly severe in the later stages. Only during the initial fever stage, if diarrhea stops spontaneously as the fever subsides, is this considered an auspicious sign. After black spots appear until scabs form, the toxic qi has all been expressed on the surface. At this time, sufficient Yuan Qi (Primordial Qi) must be充盈 (filled/abundant) internally, and the stool must be firm, so that it can support the expulsion of toxins and facilitate their successful resolution. If even slight diarrhea occurs, the Middle Qi (Spleen/Stomach Qi) will become weak, leading to various complications and disasters. If diarrhea appears after the rash first emerges, it will be difficult for the lesions to rise and fill with pus; if diarrhea occurs after the lesions have risen, the pus will stagnate during diarrhea and only fill when diarrhea stops; if diarrhea occurs after the lesions have filled with pus, it will lead to involution, abnormal scabbing, internal ulceration, and internal decay, among other symptoms. This truly concerns life and death and is most terrifying. Nowadays, it is common to see cases ruined by improper medication and misdiagnosis, damaging Spleen Qi to the point of being incurable. These practitioners still claim they want to expel toxins through diarrhea, believing diarrhea is harmless. This is deceptive and ignorant; no quackery is worse than this.
In treating diarrhea caused by chickpox/rash, the key lies in distinguishing between Cold and Heat patterns. Heat patterns are necessarily due to excess Dampness Stagnation, while Cold patterns are necessarily due to insufficiency of Yuan Yang (Primordial Yang). However, nine out of ten cases of diarrhea are Deficiency patterns, with very few being Excess Heat. Therefore, whenever diarrhea, vomiting, and abdominal pain are observed without other Excess Heat symptoms, regardless of whether it is before or after the eruption of the rash, one should promptly employ warming methods to rescue the Spleen and Kidney. This is the general principle and requires careful examination; losing the true nature and misdiagnosing will result in death.
1. Deficiency-Cold Diarrhea: Cases presenting without significant heat, aversion to cold drinks, non-rapid and non-full pulse, absence of abdominal heat/bloating, absence of chest restlessness, reduced appetite, and sudden spontaneous loose stools all belong to Deficiency-Cold. One must absolutely avoid recklessly using cold-cooling agents to further injure Spleen Earth, which would inevitably lead to incurability. Suitable formulas include Weiyin Decoction (Stomach Warming Decoction), Yangzhong Decoction (Nourishing the Center Decoction), Wu Junzi Decoction (Five Gentlemen Decoction), Lizhong Decoction (Regulate the Middle Decoction), or Sijunzi Decoction (Four Gentlemen Decoction), chosen according to circumstances. If there is slight stagnation and bloating in the abdomen causing diarrhea, Liuwei Yigong Decoction (Six-Ingredient Extraordinary Efficacy Decoction) or Wuwei Yigong Powder (Five-Ingredient Extraordinary Efficacy Powder) added with Amomum Fruit (Sharen) is suitable. If diarrhea is accompanied by vomiting and pain with Qi stagnation, Yangzhong Decoction added with Clove (Dingxiang) and Aucklandia Root (Muxiang), or a combination of Sijunzi Decoction and Erxian San (Two Immortals Powder) is suitable. If diarrhea presents with slight blueness at the Shan Gen (root of the nose) and lips/mouth, or slight coldness at the mouth/nose, cool hands/feet, slightly cold fingertips, pale yellow or greenish-white stool color, and sleeping with eyes partially open, these are signs of Spleen-Kidney Deficiency-Cold. Without urgently rescuing the Mingmen Fire (Gate of Life Fire), effectiveness will not be seen. The main prescriptions should be Weiguan Decoction (Stomach Gate Decoction) or Linyin Decoction (Nourishing Yin Decoction); Chen's Shierwei Yigong San (Twelve-Ingredient Extraordinary Efficacy Powder) is also acceptable. If diarrhea is severe and warming Spleen medicines fail, then Weiguan Decoction or Linyin Decoction must be used as the main treatment. For chronic diarrhea with slipping and inability to stop, Weiguan Decoction, Weiyin Decoction, or Chen's Shierwei Yigong San can be taken with Wude Pill (Five Virtues Pill) or Myristica Seed Pill (Roudoukou Pill). If the Stomach is not originally deficient, but diarrhea is caused by Cold-Damp injuring the Spleen or excessive water intake, Zuoguan Decoction (Assisting the Gate Decoction), Yifu Decoction (Suppressing and Supporting Decoction), Yihuang San (Yellow Protecting Powder) added with Polyporus (Zhuling) and Alisma Rhizome (Zexie), or Wuling San (Five-Ling Powder) are all excellent choices.
2. Accumulated Heat Diarrhea: This is rare but occasionally occurs. However, there must be evidence of Heat patterns before using clearing and draining herbs. Examples include a full and rapid pulse, high fever, intense thirst preferring cold drinks and disliking heat, restlessness with profuse sweating, chest fullness with coarse breathing, swollen red-purple lesions, hot/red mouth and nose, or painful/difficult urination—all are Heat signs. Furthermore, Heat diarrhea tends to be sudden and severe, while Cold diarrhea tends to be gradual and slow, allowing for differentiation. However, when treating Heat, one must observe the degree of Fire pathogen to ensure the medicine does not exceed the illness, lest it injure the Spleen and cause harm. For internal accumulation of Damp-Heat with difficult urination, mild fever, and diarrhea, Wuling San, Siling San (Four-Ling Powder), or Xiaoliqing Yin (Minor Clearing Decoction) added with Akebia Stem (Mutong) is suitable. If Damp-Heat is slightly more severe, causing confusion between clear and turbid fluids leading to diarrhea, Siling San added with Ginger-fried Coptis Rhizome (Huanglian), or combined with Huangqin Tang (Scutellaria Decoction), is suitable. If diarrhea is caused by food retention with a strong pulse and robust Qi, treat from the Heat perspective using Huangqin Tang added with Huanglian. If Heat is in the Lower Jiao (Lower Burner) with red, scanty, and painful urination accompanying diarrhea, Daliquing Yin (Major Clearing Decoction) or combined with Yiyuan San (Benefit Origin Powder) is suitable. If Damp-Heat is in the Spleen, with diarrhea, internal heat, and abdominal pain, Xianglian Wan (Aucklandia-Coptis Pill) is suitable. If cheeks are red, body is hot, headache and sore throat occur, along with mouth ulcers, restlessness, and diarrhea, this is a Yangming Fire pattern; Xiexuang San (Draining Yellow Powder) is suitable. If Damp-Heat is in the Spleen, with diarrhea and vomiting, Huangqin Tang added with Pinellia Tuber (Banxia) and Fresh Ginger (Shengjiang), or Banxiaren Tang (Large Pinellia Decoction) from *Yuyao Fang* added with Huangqin, is suitable. If internal heat diarrhea is accompanied by Qi Deficiency, Sijunzi Decoction added with Paeonia Root (Shaoyao), Huanglian, and Muxiang is suitable.
3. Thirst: Thirst is a common accompaniment to diarrhea because fluid loss from below leads to dryness above. Thus, patients with diarrhea often experience dry mouth and thirst. However, "dryness" (Gan) differs from "thirst" (Ke). Thirst implies a desire to drink, whereas dryness implies no desire to drink. Thirst belongs to Yang, and dryness belongs to Yin; this is the distinction. Some desire to drink water, indicating a Fire (Heat) pattern. Some desire to drink hot soup, indicating no Fire pattern. Some desire to drink but cannot consume much, or desire coolness but fear cold in the chest and abdomen; these are not Fire patterns. Since thirst itself has Yin-Yang distinctions, how much more so for those who are merely dry without thirst? This is actually due to Water Deficiency (Yin Deficiency). Treating it as Fire will rarely fail to cause harm. Therefore, for chronic diarrhea resulting in fluid loss and thirst, one must ascertain that it is not Heat and must tonify the Water (Yin).
Master Cheng said: Diarrhea must be distinguished by Cold and Heat. In Cold patterns, urine is clear; Lizhong Decoction or Shenling Baizhu San (Ginseng, Poria, and Atractylodes Macrocephala Powder) is suitable. However, Atractylodes Macrocephala Rhizome (Baizhu) and Poria (Fuling) are not suitable for diarrhea accompanied by blistering, due to their draining properties. According to this view, even draining methods are contraindicated in treating chickpox; how much less should one recklessly use dispersing and reducing methods to damage Qi, Blood, and Body Fluids?
Master Chen said: Frequent diarrhea consumes fluids, causing Qi and Blood to fail to nourish the body. Even if the rash rises, it will be difficult to resolve. Symptoms such as warm body but abdominal distension, shortness of breath, teeth grinding, restlessness, and delirium are difficult to treat because excessive loss of grain essence leads to exhaustion of Body Fluids, often resulting in death. Quickly administer Shiyiwei Muxiang San (Eleven-Ingredient Aucklandia Powder) or Shierwei Yigong San (Twelve-Ingredient Extraordinary Efficacy Powder).
Master Wan said: If diarrhea occurs before the rash erupts, the pathogen has merged into the interior, representing an Excess pattern; treatment should focus on clearing toxins. If diarrhea occurs after the rash erupts, the pathogen has reached the exterior, and the interior is Deficient; treatment should address the Deficiency. The greatest taboo in chickpox is internal Deficiency with diarrhea. If warming and consolidating methods do not cure it, this is an incurable condition.