【纲】仲景曰。太阳病。发热而渴。不恶寒者。为温病。
【目】李中梓曰。渴之为病。或因热耗津液。或因汗下过多。各不同也。
鳌按。此概言太阳之温症。四时有之。非专指春温也。所以名之曰温者。以内外皆热也。发热
为外热。渴为内热。所以别于中风伤寒也。
【纲】仲景曰。形作伤寒。其脉不弦紧而弱。弱者必渴。被火者必谵语。弱者发热脉浮。解之。
当汗出而愈。
【目】许叔微曰。此乃夹虚伤寒症也。脉弱者。阴不足。阳气陷于阴分。故必渴。渴者。液虚
故也。
【纲】仲景曰。伤寒心下有水气。咳而微喘。发热不渴。小青龙汤主之。服汤已渴者。此寒去
欲解也。
【目】成无己曰。凡得病。反能饮水。此为欲愈之病。其不晓病者。但闻病者能饮水自瘥。小
渴者。乃强与饮之。因成大祸。不可复救。然则悸动也。支结也。喘咳噎哕。干呕下利。肿满。小
便不利数者。皆是饮水过伤。当须识此。勿误也。
柯琴曰。此正欲明服汤后渴者是解候也。恐人服止渴药。反滋水气。故先提不渴二字作眼。后
提出渴者以明之。若寒既欲解而更服之。不惟不能止渴。且重亡津液。转属阳明而成胃实矣。
【纲】仲景曰。中风发热。六七日不解而烦。有表里症。渴欲饮水。水入则吐者。名曰水逆。
五苓散主之。多服暖水。汗出愈。
【目】朱肱曰。初戒太阳症无汗而渴者。不可与白虎汤。问曰。太阳病汤。终不可与白虎汤耶。
曰。太阳症得汗后。脉洪
大而渴者。方可与之。脉浮而渴。属太阳。若阳明少阳少阴。俱有渴症。
张元素曰。此症因于发汗过多。水入则吐者。以心下有水气。故水饮拒绝于外也。五苓者。本
因水气不舒而设。是小发汗。不是生津液。是逐水气。不是利水道。
【纲】仲景曰。太阳病。发汗后。大汗出。胃中干。烦躁不得眠。欲得饮水者。少少与饮之。
令胃气和。则愈。若脉浮。小便不利。微热消渴者。五苓散主之。太阳病。其人发热汗出。不恶寒
而渴者。此转属阳明也。渴欲饮水者。少少与之。但以法救之。宜五苓散。
【目】朱肱曰。凡病非大渴不可与水。若小渴咽干者。只小呷滋润之。令胃中和。若大渴烦躁
者。能饮一斗。只与五升。若全不与。则干燥。无由作汗。发喘而死。常人见因渴饮水得汗。小渴。
遂剧与之。致停饮心下。满结喘死者甚众。当以五苓散。或陷胸丸主之。金匮云。得时气至五六
日。而渴欲饮水不得。多不当与也。何也。以腹中热尚少。不能消之。便更作病矣。至七八日。大
渴欲饮水。犹当根据症与之。常令不足。勿极意也。凡人但见仲景云。得病反能饮水。此为欲愈。遂
小渴者。乃强饮之。因成其祸。不可胜数。大抵伤寒水气。皆因饮水过多所致。水停心下。气上乘
心。则为悸为喘。结于胸胁。则为水结胸。胃中虚冷。则为呕为哕。冷气相薄。则为噎。上迫于肺。
则为咳。渍入肠中。则为利。邪热所薄。蓄于下焦。则为小便不利。少腹满。或里急。溢于皮肤
间。则为肿也。
王好古曰。邪气在表。犹未作热。故不渴。邪气初传入里。热气散漫未收。熏蒸焦膈。搏耗津
液。遂成渴也。病患渴欲饮水。少少与之。但以法救者。恐饮水过多。积不能消。复为停饮诸疾也。
柯琴曰。前条上半截。与后条同义。前条在大汗后。后条在未汗前。即是太阳温病。要知太阳
温病。即是阳明来路。其径最捷。不若伤寒中风。止从亡津液而后转属也。饮水是温病大法。庶不
犯汗吐下温之误。五苓又是治饮多之法。前条。便是转属阳明症。
【纲】仲景曰。太阳病。饮水多。小便利者。必心下悸。小便少者。必苦里急也。伤寒汗出。而心下悸。渴者。五
苓散主之。不渴者。茯苓甘草汤主之。本以下之。故心下痞。与泻心汤。痞不解。其人渴而口燥烦。小便不利者。五苓
散主之。
【目】陶华曰。渴者。里有热也。津液为热所耗。伤寒六七日传至厥阴为消渴者。谓饮水多而小便少。乃热能消水
也。朱氏云。脉浮而渴。属太阳。有汗而渴。属阳明。自利而渴。属少阴。至于厥阴。则又热之极矣。太阳无汗若渴。
忌白虎。宜柴胡。阳明多汗而渴。宜竹叶石膏。若先呕后渴。则为欲解。当与之水。先渴后呕。则为水停。赤茯苓汤。
当根据此议。勿令误也。
鳌按。第二条渴不渴。双顶心下悸。是汗出后既心下悸矣。而又有或渴或不渴者。二方皆因心下水气而设也。
【纲】仲景曰。太阳病。中风。以火劫发汗。邪风被火热。血气流溢。失其常度。两阳相熏灼。身体则枯燥。但头
汗出。齐颈而还。其身发黄。阳盛则欲衄。阴虚则小便难。阴阳俱虚竭。则腹满而喘。口渴咽烂。或不大便。久则谵语。
甚者至哕。手足躁扰。捻衣摸床。小便利者。其人可治。
【目】鳌按。此言火灸之变。即火逆症。因火灸不如法。以致变生种种。惟以小便利者为可治。则知火逆之症。必
以阴为主。最忌阴竭。犹之伤寒病以阳为主。最忌阳亡也。故中间阳盛阴虚四字。是火逆症之纲领。阳盛则伤血。阴虚
则亡津。又伤寒书之大纲领也。
【纲】仲景曰。湿家。但头汗出。背强。欲得被覆。向火。若下之。则哕。胸满。小便不利。舌上如苔者。以丹田
有热。胸中有寒。渴欲得水。而不能饮。口燥烦也。
【目】李梃曰。热在表则不渴。热入里则渴。耗夺津液而然也。然有渴必有烦者。肾主水。热深则水竭而渴。肝木
挟心。火以生烦。故厥阴六七日。饮水多而小便少者。谓之消渴。渴欲饮水为欲愈。传经已尽也。
鳌按。背强恶寒。尚属太阳。寒湿本当汗解。不汗而下。必致阳气扰上焦而满。伤中焦而哕。伤
下焦而小便不利。既三焦受病矣。口燥烦而舌上苔。由丹田之有热。不能饮水。是湿犹在中。当
从五苓散去桂枝易肉桂。
【纲】仲景曰。太阳中暑。其人汗出恶寒。身热而渴也。
【目】柯琴曰。中暑夹寒。有得之乘凉者。阴寒先着于肌肤。而暑气内伤于心脉。故恶寒身热
汗出而渴也。清暑益气汤。东垣得之矣。
【纲】张仲景说：太阳病（太阳经受邪所致的病证），出现发热且口渴，不恶寒（不怕冷）的，称为温病（一种初起即见热象的外感热病）。
【目】李中梓说：口渴这一病症，有的是因为热邪耗伤津液所致，有的是因为发汗或攻下过度所致，原因各不相同。
沈金鳌按语：这里概括地论述了太阳病的温症，四季都有发生，并非专指春季的温病。之所以称之为“温”，是因为体内和体表都有热邪。发热属于外热，口渴属于内热，因此将其与中风（太阳中风证）和伤寒（太阳伤寒证）区别开来。
【纲】张仲景说：症状表现像伤寒，但脉象不弦紧而虚弱。脉弱的人必定口渴，如果误用火疗（如艾灸、火熏等），必定会出现谵语（神志不清，胡言乱语）。如果脉弱且发热、脉浮，应当采用解表法治疗，当出汗后痊愈。
【目】许叔微说：这是夹虚伤寒症（体质虚弱兼感寒邪的病证）。脉象弱，说明阴液不足，阳气陷入阴分，所以必定口渴。口渴的原因，是津液亏虚。
【纲】张仲景说：伤寒导致心下有停水气，咳嗽且轻微气喘，发热但不口渴，用小青龙汤主治。服药后感到口渴的，这是寒邪已去、病情即将解除的表现。
【目】成无己说：凡是患病，反而能饮水，这是疾病将要痊愈的迹象。那些不懂医理的人，只听说病人能饮水就会自愈，对于轻微口渴的病人，就强行让他们大量饮水，结果造成大祸，无法挽救。然而，心悸、支饮结聚、喘咳呃逆、干呕下利、肿胀满闷、小便不利频数等症状，都是因为饮水过多受伤造成的，必须认清这一点，不要误治。
柯琴说：这正是为了阐明服药后出现口渴是病情缓解的征候。担心人们服用止渴药，反而助长水气，所以先提出“不渴”二字作为关键，随后提出“渴者”来加以说明。如果寒邪既已欲解却再服药，不仅不能止渴，反而会进一步损耗津液，转而归属于阳明经，形成胃实热证。
【纲】张仲景说：中风发热，六七天未解且心烦，有表证和里证，想喝水，但水喝进去就吐出的，名叫水逆（因水饮内停，气化不利，水入即吐的症状）。用五苓散主治。多服暖水，出汗后即可痊愈。
【目】朱肱说：起初要告诫，太阳病无汗而口渴的，不可给予白虎汤。问：太阳病的汤剂，终究都不能给白虎汤吗？答：太阳病在发汗后，脉象洪大且口渴的，才可以给予白虎汤。脉浮且口渴，属于太阳病；至于阳明、少阳、少阴，也都会有口渴的症状。
张元素说：此症是因为发汗过多，水喝进去就吐，是因为心下有停水气，所以水饮被拒绝于外。五苓散这个方子，原本是因水气不舒而设立的，它是小发汗，不是生津液；它是驱逐水气，不是通利水道。
【纲】张仲景说：太阳病，发汗后，大汗出，胃中干燥，烦躁不得安眠，想要喝水的，少量多次给予饮水，使胃气调和，就会痊愈。如果脉浮，小便不利，微热且消渴（极度口渴，饮水不解）的，用五苓散主治。太阳病，病人发热汗出，不恶寒而口渴的，这是转属阳明病。想喝水的，少量多次给予，只要依法救治即可，适宜用五苓散。
【目】朱肱说：一般生病，如果不是大渴，不可以随意给水。如果是小渴咽干，只需小口啜饮滋润之物，使胃中和顺。如果是大渴烦躁，能喝一斗水，只给五升。如果完全不给水，就会干燥，无法作汗，导致发喘而死。常人看到因口渴饮水而出汗，若是小渴，就剧烈地给予饮水，导致水饮停滞在心下，胀满结聚而喘死的很多。应当用五苓散，或者陷胸丸主治。《金匮要略》说：患时气病到了五六天，口渴想喝水却得不到，大多不应给予。为什么呢？因为腹中热邪尚少，不能消化水分，反而会成为新的病患。到了七八天，大渴想喝水，仍应根据症状给予，常令其水量不足，不要刻意让其喝足。世人只见张仲景说：“得病后反而能饮水，这是欲愈之兆”，于是对轻微口渴的病人强行喂水，因此造成的祸害，数不胜数。大抵伤寒的水气病，都是因饮水过多所致。水停在心下，气上乘于心，就会成为心悸或气喘；结于胸胁，就成为水结胸；胃中虚冷，就会呕吐或呃逆；冷气相搏，就会噎塞；上迫于肺，就会咳嗽；渗入肠中，就会下利；邪热逼迫，蓄积在下焦，就会小便不利、少腹胀满，或者里急后重；溢于皮肤之间，就会浮肿。
王好古说：邪气在体表，尚未化热，所以不渴。邪气初入里，热气散漫未收敛，熏蒸膈膜，搏击耗伤津液，遂成口渴。病人想喝水，少量给予，只是依法救治，是担心饮水过多，积聚不能消化，又成为停饮的各种疾病。
柯琴说：前一条的上半部分，与后一条意义相同。前一条是在大汗之后，后一条是在未发汗之前，这就是太阳温病。要知道太阳温病，就是转入阳明的捷径，不像伤寒和中风，只有通过亡失津液后才转属阳明。饮水是治疗温病的大法，这样才不会犯汗、吐、下、温法的错误。五苓散又是治疗饮水过多的方法。前一条，就是转属阳明症的例子。
【纲】张仲景说：太阳病，饮水多，小便通畅的，必定心下悸动；小便少的，必定苦于里急（小腹拘急不适）。伤寒汗出，且心下悸动、口渴的，用五苓散主治；不口渴的，用茯苓甘草汤主治。本因误下导致心下痞硬，给予泻心汤，痞硬未解，其人口渴且口燥心烦，小便不利的，用五苓散主治。
【目】陶华说：口渴，是有里热。津液被热邪耗伤。伤寒六七天传至厥阴经出现消渴的，是指饮水多而小便少，这是热能消水。朱氏说：脉浮而口渴，属于太阳病；有汗而口渴，属于阳明病；自利（腹泻）而口渴，属于少阴病。至于厥阴经，则是热邪极盛。太阳病无汗若口渴，忌用白虎汤，宜用柴胡剂。阳明病多汗而口渴，宜用竹叶石膏汤。如果先呕吐后口渴，则是欲解之兆，应当给予水喝；先口渴后呕吐，则是水饮停留，应用赤茯苓汤。应当依据此议，不要误治。
沈金鳌按语：第二条关于渴与不渴，是双重承接“心下悸”。意思是汗出后已经心下悸动，而又存在或渴或不渴的情况。这两个方子都是因心下有水气而设立的。
【纲】张仲景说：太阳病，中风，用火劫法发汗，邪风被火热所迫，血气流溢，失去常态。两阳（风火）相互熏灼，身体就会枯燥，只有头部出汗，齐颈而还（不到颈部），身体发黄。阳盛则想流鼻血，阴虚则小便困难。阴阳俱虚竭，就会腹满而喘，口渴咽烂，或者不大便。时间久了会谵语，严重的甚至呃逆，手足躁扰，捻衣摸床（无意识地抓摸衣物和床沿）。如果小便通利的，这个人还可以治愈。
【目】沈金鳌按语：这是论述火灸变证，即火逆症。因为火灸方法不当，以致产生种种变证。只有以小便利为可治，就知道火逆症必须以阴液为主，最忌讳阴竭。就像伤寒病以阳气为主，最忌讳阳亡一样。所以中间的“阳盛阴虚”四字，是火逆症的纲领。阳盛则伤血，阴虚则亡津，这也是伤寒书的总纲领。
【纲】张仲景说：湿家（素患湿病的人），只有头部出汗，背部僵硬，想要盖被子、靠近火源取暖。如果误用下法，就会呃逆，胸满，小便不利，舌上有苔，这是因为丹田有热，胸中有寒，想喝水但不能喝，口燥心烦。
【目】李梃说：热在体表则不渴，热入里则渴，这是耗夺津液所致。然而有渴必有烦，肾主水，热深则水竭而渴；肝木挟心火，火生烦，所以厥阴病六七天，饮水多而小便少的，称为消渴。渴欲饮水是欲愈之兆，表示传经已尽。
沈金鳌按语：背强恶寒，尚属于太阳病。寒湿本当用汗法解表，若不汗而下之，必致阳气扰乱上焦而胸满，损伤中焦而呃逆，损伤下焦而小便不利。既然三焦都受病了，口燥烦且舌上有苔，是由于丹田有热，不能饮水，这说明湿邪仍在中焦，应当从五苓散去桂枝，改用肉桂。
【目】柯琴说：中暑夹寒，有的因乘凉所致，阴寒先附着于肌肤，而暑气内伤心脉，所以恶寒、身热、汗出且口渴。清暑益气汤，李东垣对此已有论述。
[Outline] Zhang Zhongjing said: In Taiyang disease (a syndrome caused by pathogenic factors invading the Taiyang meridian), if there is fever and thirst, without aversion to cold, it is called Warm Disease (an external febrile disease characterized by early heat signs).
[Commentary] Li Zhongzi said: Thirst as a symptom may be caused by heat consuming body fluids, or by excessive sweating or purging; the causes vary.
Shen Jin'ao's note: This generally discusses Warm Syndrome of Taiyang, which occurs in all four seasons, not specifically referring to Spring Warmth. It is named "Warm" because both internal and external aspects involve heat. Fever represents external heat, while thirst represents internal heat; thus, it is distinguished from Wind Strike (Taiyang Wind Strike syndrome) and Cold Damage (Taiyang Cold Damage syndrome).
[Outline] Zhang Zhongjing said: The presentation resembles Cold Damage, but the pulse is not wiry and tight; instead, it is weak. A weak pulse indicates inevitable thirst. If treated with fire therapy (such as moxibustion or heat application), delirium will certainly occur. If the pulse is weak, accompanied by fever and floating, treatment should aim at releasing the exterior; recovery follows when sweat appears.
[Commentary] Xu Shuwei said: This is a case of Cold Damage with deficiency. A weak pulse indicates insufficient Yin fluids, causing Yang Qi to sink into the Yin aspect, hence the inevitable thirst. Thirst results from fluid depletion.
[Outline] Zhang Zhongjing said: In Cold Damage, if there is water retention under the heart (epigastrium), leading to cough and slight wheezing, fever, but no thirst, Xiao Qing Long Tang (Minor Blue Dragon Decoction) is indicated. If thirst occurs after taking the decoction, this indicates that the cold pathogen is departing and the condition is resolving.
[Commentary] Cheng Wuji said: Generally, if a patient can drink water despite illness, it signals impending recovery. Those unfamiliar with medicine may hear that drinking leads to self-healing and force-feed patients who are only slightly thirsty, causing severe harm that cannot be remedied. However, palpitations, fluid retention binding in the chest, wheezing/coughing, hiccupping, dry retching, diarrhea, swelling/fullness, and frequent urination with difficulty are all injuries caused by excessive water intake. One must recognize this to avoid mismanagement.
Ke Qin said: This passage clarifies that thirst after medication is a sign of resolution. It warns against using thirst-quenching medicines that might exacerbate water retention. By highlighting "no thirst" first and then addressing "thirst," it explains the mechanism. If one continues medication after the cold has resolved, it will not quench thirst but further deplete fluids, potentially transferring to the Yangming stage and forming stomach excess heat.
[Outline] Zhang Zhongjing said: In Wind Strike with fever, if unresolved after six or seven days with irritability, presenting both exterior and interior symptoms, where the patient desires water but vomits immediately upon ingestion, this is named Water Reversal (symptoms of vomiting water due to impaired qi transformation and fluid retention). Wu Ling San (Five-Ingredient Powder with Poria) is indicated. Drinking warm water frequently and inducing sweat leads to recovery.
[Commentary] Zhu Gong said: Initially, it must be cautioned that for Taiyang disease with no sweat and thirst, Bai Hu Tang (White Tiger Decoction) is contraindicated. Question: Is Bai Hu Tang never used for Taiyang? Answer: Only after sweating, if the pulse is surging and large with thirst, may Bai Hu Tang be used. A floating pulse with thirst belongs to Taiyang. However, thirst also occurs in Yangming, Shaoyang, and Shaoyin syndromes.
Zhang Yuansu said: This condition arises from excessive sweating. Vomiting upon drinking water is due to water retention under the heart, rejecting the ingested fluid. Wu Ling San was designed for stagnant water qi; it induces mild sweating rather than generating fluids, and expels water qi rather than promoting diuresis alone.
[Outline] Zhang Zhongjing said: In Taiyang disease, after sweating, if profuse sweating occurs leaving the stomach dry, causing irritability and insomnia, and the patient desires water, give small amounts of water frequently to harmonize the stomach qi, leading to recovery. If the pulse is floating, urination is difficult, with slight fever and extreme thirst (Xiao Ke), Wu Ling San is indicated. In Taiyang disease, if the patient has fever, sweating, no aversion to cold, and thirst, this indicates transfer to Yangming. For those desiring water, give small amounts and treat according to principles; Wu Ling San is appropriate.
[Commentary] Zhu Gong said: Generally, do not give water unless there is extreme thirst. For slight thirst with dry throat, sip moistening liquids to harmonize the stomach. For extreme thirst and irritability allowing consumption of one dou, give only five sheng. Withholding water entirely causes dryness, inability to sweat, asthma, and death. Laypeople often see that drinking water induces sweat and overfeed patients with slight thirst, causing fluid retention under the heart, fullness, and fatal asthma. Use Wu Ling San or Xian Xiong Wan (Trap-Chest Pill). The *Jin Gui Yao Lue* states: In seasonal febrile diseases, around day five or six, if the patient wants water but cannot get it, do not give it. Why? Because internal heat is insufficient to transform the water, creating new pathology. By day seven or eight, if there is extreme thirst, give water according to symptoms, but ensure intake is insufficient, do not force completion. People mistakenly interpret Zhang Zhongjing’s statement "being able to drink after falling ill indicates recovery" as a license to force-feed slightly thirsty patients, causing countless disasters. Most water-related issues in Cold Damage stem from excessive drinking. Water stagnating under the heart pushes qi upward to the heart, causing palpitations or asthma; binding in the chest/hypochondrium causes Water Binding Chest; cold deficiency in the stomach causes vomiting or hiccupping; cold qi clashing causes dysphagia; pressing on the lungs causes cough; seeping into intestines causes diarrhea; pathogenic heat forcing accumulation in the Lower Jiao causes urinary difficulty, lower abdominal fullness, or tenesmus; overflowing into skin causes edema.
Wang Haogu said: When pathogens are in the exterior and have not yet generated heat, there is no thirst. As pathogens enter the interior, scattered heat steams the diaphragm, clashing with and consuming fluids, resulting in thirst. Patients desiring water should receive small amounts; this cautious approach prevents excessive intake that could accumulate and cause fluid retention diseases.
Ke Qin said: The first half of the previous paragraph shares meaning with the latter. The former occurs after profuse sweating; the latter before sweating—this is Taiyang Warm Disease. Note that Taiyang Warm Disease is the direct pathway to Yangming, unlike Cold Damage or Wind Strike, which require fluid depletion before transferring. Hydration is the major principle for treating Warm Disease, avoiding errors of sweating, vomiting, purging, or warming. Wu Ling San treats excessive fluid intake. The previous paragraph exemplifies transfer to Yangming.
[Outline] Zhang Zhongjing said: In Taiyang disease, if water intake is high and urination is free, palpitations under the heart will definitely occur. If urination is low, distress from lower abdominal urgency will definitely occur. In Cold Damage with sweating, if there is palpitation under the heart and thirst, Wu Ling San is indicated; if there is no thirst, Fu Ling Gan Cao Tang (Poria and Licorice Decoction) is indicated. Originally due to incorrect purging causing epigastric fullness/stiffness, given Xie Xin Tang (Drain the Epigastrium Formulas), but if fullness persists, and the patient has thirst, dry mouth, irritability, and urinary difficulty, Wu Ling San is indicated.
[Commentary] Tao Hua said: Thirst indicates interior heat consuming fluids. In Cold Damage transmitting to Jueyin around day six or seven, manifesting as extreme thirst (Xiao Ke), it means drinking much but urinating little, indicating heat consumes water. Zhu stated: Floating pulse with thirst belongs to Taiyang; sweating with thirst belongs to Yangming; spontaneous diarrhea with thirst belongs to Shaoyin. Jueyin represents extreme heat. For Taiyang with no sweat and thirst, avoid Bai Hu Tang; use Chai Hu formulas. For Yangming with sweating and thirst, use Zhu Ye Shi Gao Tang (Bamboo Leaf and Gypsum Decoction). Vomiting followed by thirst indicates resolution; give water. Thirst followed by vomiting indicates water retention; use Chi Fu Ling Tang (Red Poria Decoction). Adhere to these principles to avoid error.
Shen Jin'ao's note: The second item regarding thirst/non-thirst doubly connects to "palpitation under the heart." It means palpitation exists post-sweating, with variations of thirst or no thirst. Both formulas address water qi under the heart.
[Outline] Zhang Zhongjing said: In Taiyang disease with Wind Strike, if fire therapy is used to induce sweating, wind pathogens combined with fire cause blood and qi to overflow, losing their normal course. The dual yang (wind and fire) scorch each other, causing body dryness. Sweat appears only on the head, stopping at the neck. The body turns yellow. Excess Yang leads to epistaxis; Yin deficiency leads to difficult urination. If both Yin and Yang are depleted, abdominal fullness and asthma occur, along with thirst, sore throat, constipation, delirium, severe cases developing hiccups, restlessness of hands and feet, and unconscious grasping at clothes and bed sheets. If urination is free, the patient is treatable.
[Commentary] Shen Jin'ao's note: This discusses complications from moxibustion, known as Fire Reversal Syndrome. Improper fire therapy causes various transformations. Treatability depends on free urination, indicating that Fire Reversal relies on Yin; Yin exhaustion is most feared, just as Yang collapse is feared in Cold Damage. Thus, "Yang excess and Yin deficiency" are the key principles of Fire Reversal. Yang excess injures blood; Yin deficiency loses fluids. These are also overarching principles in Cold Damage texts.
[Outline] Zhang Zhongjing said: In patients prone to dampness, sweat appears only on the head, the back is stiff, and they desire covering and warmth near fire. If incorrectly purged, hiccups, chest fullness, urinary difficulty, and a tongue coating appear. This is due to heat in the Dantian (lower abdomen) and cold in the chest, causing desire to drink but inability to swallow, with dry mouth and irritability.
[Commentary] Li Ting said: Heat in the exterior does not cause thirst; heat entering the interior causes thirst due to fluid depletion. Thirst is always accompanied by irritability. The Kidney governs water; deep heat exhausts water causing thirst. Liver Wood supports Heart Fire, generating irritability. Thus, in Jueyin disease around day six or seven, drinking much but urinating little is called Extreme Thirst. Desire to drink indicates resolution, meaning transmission is complete.
Shen Jin'ao's note: Back stiffness and aversion to cold still belong to Taiyang. Cold-dampness should be resolved via sweating. Purging without sweating disturbs Yang in the Upper Jiao (causing fullness), damages the Middle Jiao (causing hiccups), and damages the Lower Jiao (causing urinary difficulty). With all three Jiaos affected, dry mouth, irritability, and tongue coating indicate heat in the Dantian. Inability to drink suggests dampness remains in the Middle Jiao. Treatment should modify Wu Ling San by removing Cinnamon Twig and adding Cinnamon Bark.
[Outline] Zhang Zhongjing said: In Summerheat affecting Taiyang, the patient sweats, feels aversion to cold, has fever, and thirst.
[Commentary] Ke Qin said: Summerheat combined with cold may result from cooling off; yin-cold attaches to the skin/muscles first, while summerheat internally injures the Heart vessels, causing aversion to cold, fever, sweating, and thirst. Qing Shu Yi Qi Tang (Clear Summerheat and Benefit Qi Decoction), developed by Li Dongyuan, addresses this.