热病之脉，亦随其经而取之。发于太阳脉浮紧，发于阳明脉浮长，发于少阳脉弦数。大率发于三阳者多，发于三阴
者少，亦有所因也。（治根据温病条下。若表邪传进三阴者，治法与伤寒条内下证同。若脉沉小足冷者，亦发于阴，则难
治也。）
大抵热病比温病尤加热也，脉得洪大有力，或滑数有力，乃为病脉相应，谓之可治；若细小无力，谓之难医。（人
虚脉弱者，主扶元气，兼解邪热，不可峻攻。）治表证在者，治例与温病同。若夹暑、夹内伤生冷、饮食停滞，随证施
治之。中暑与热病外证相似，但热病者脉盛，中暑者脉虚，以此别之。《甲乙经》云∶脉盛身寒，得之伤寒；脉虚身热，
得之伤暑。盖寒伤形而不伤气，所以脉盛；热伤气而不伤形，所以脉虚。（此辨暑、热，有暴感、伏气，而脉之盛虚异
焉。）暑、 皆脉虚，面垢自汗烦渴。静而热伤心脾为中暑，与夏热病相似，但热病脉洪紧，中暑脉细数而沉。动而热
伤太阳为中 ，脉浮似夏伤风，但汗出恶风，身热而不渴者，伤风也。身热而渴者，中 也。（后人所谓中暑，多指夏
月阴证而言。）夏月有四证∶伤寒伤风，脉证互见；中暑热病，疑似难明。若脉紧恶寒，谓之伤寒；脉缓恶风，谓之伤
风；脉盛壮热，谓之热病；脉虚身热，谓之伤暑。以此别之也。
热病一二日，泻利腹满热甚者死。
三四日，目昏谵语，热甚脉小者死。
五六日，舌本焦黑，燥渴者死。
七八日，衄血吐血下血，燥热脉大者死。
八九日，发痉兼昏沉者死。
凡热病脉，促、结、伏、沉、小，皆难治。热不得汗，脉躁急，亦难治。已得汗，而热反盛，脉躁急者死也。
热病的脉象，也随着病变所在的经络来诊察。病发于太阳经的，脉象浮紧；病发于阳明经的，脉象浮长；病发于少阳经的，脉象弦数。大抵而言，病发于三阳经（太阳、阳明、少阳）的情况较多，病发于三阴经（太阴、少阴、厥阴）的情况较少，这也是由致病原因决定的。（治疗方法依据温病条下的规定。如果是表邪传入三阴经的，治法与伤寒条内下证的治疗方法相同。如果脉象沉小且足部发冷的，也是病发于阴经，则难以治疗。）
大体上说，热病比温病更加严重，脉象表现为洪大有力，或滑数有力，这才是病脉与病情相应，称为可治；如果脉象细小无力，称为难医。（对于人体虚弱、脉象微弱者，主治原则是扶助元气，兼以解除邪热，不可使用猛烈攻伐的方法。）治疗表证存在的，治疗原则与温病相同。如果夹杂暑邪、夹带内伤生冷食物、或饮食停滞，则根据具体证候施治。中暑与热病的外在症状相似，但热病患者脉象盛大，中暑患者脉象虚软，以此加以区别。《甲乙经》说：脉象盛大而身体发寒，是得之伤寒；脉象虚软而身体发热，是得之伤暑。这是因为寒邪伤害形体而不伤害气，所以脉象盛大；热邪伤害气而不伤害形体，所以脉象虚软。（这是辨别暑邪和热邪，有暴感（即时感受）和伏气（潜伏之气）的区别，因而脉象的盛虚有所不同。）暑邪和中风邪都导致脉虚，面色垢浊、自汗、心烦口渴。静坐时热邪伤心脾为中暑，与夏季的热病相似，但热病的脉象洪紧，中暑的脉象细数而沉。活动时热邪伤太阳经为中暍（中暑的一种），脉象浮起类似夏季伤风，但出汗、怕风、身体发热却不口渴的，是伤风。身体发热且口渴的，是中暍。（后人所谓的中暑，多指夏季的阴证而言。）夏季有四种证候：伤寒和伤风，脉象与症状相互交错；中暑和热病，容易混淆难以辨明。如果脉象紧束且怕冷，称为伤寒；脉象缓弱且怕风，称为伤风；脉象盛大且高热，称为热病；脉象虚软且身体发热，称为伤暑。以此加以区别。
热病一二日，出现腹泻、腹部胀满、高热严重的，预后不良（死）。
三四日，眼睛昏花、胡言乱语，高热且脉象小的，预后不良（死）。
五六日，舌根焦黑、极度干燥口渴的，预后不良（死）。
七八日，鼻出血、吐血、便血，燥热且脉象大的，预后不良（死）。
八九日，发生痉挛并伴有神志昏沉的，预后不良（死）。
凡是热病的脉象，出现促脉、结脉、伏脉、沉脉、小脉的，都难以治疗。热病不得汗出，脉象躁急的，也难以治疗。已经出汗，但热势反而更盛，脉象躁急的，预后不良（死）。
The pulse of heat disease is also examined according to the affected meridian. When it originates in the Taiyang (Greater Yang) meridian, the pulse is floating and tight; when it originates in the Yangming (Yang Brightness) meridian, the pulse is floating and long; when it originates in Shaoyang (Lesser Yang) meridian, the pulse is wiry and rapid. Generally speaking, cases originating in the three Yang meridians are more common, while those originating in the three Yin meridians are fewer, which is due to specific causes. (Treatment follows the regulations for warm diseases. If exterior pathogens transmit into the three Yin meridians, the treatment method is the same as the purgative indications in Shanghan Treatise. If the pulse is deep and small with cold feet, it indicates origin in the Yin, which is difficult to treat.)
Generally, heat disease is more severe than warm disease. A pulse that is surging, large, and forceful, or slippery and rapid and forceful, indicates correspondence between the pathological pulse and the condition, termed "treatable"; if the pulse is fine, small, and weak, it is termed "difficult to cure." (For patients with deficiency and weak pulses, the primary approach is to support Yuan Qi (Original Qi) while simultaneously resolving pathogenic heat; harsh attacking methods should not be used.) For cases where exterior syndromes exist, the treatment principles are the same as those for warm diseases. If complicated by summerheat, internal injury from raw/cold food, or food stagnation, treatment is administered according to the specific syndrome. Summerheat stroke resembles heat disease in external symptoms, but in heat disease the pulse is vigorous, whereas in summerheat stroke the pulse is deficient; this distinguishes them. The *Jia Yi Jing* states: "A vigorous pulse with cold body results from Cold Damage (Shanghan); a deficient pulse with hot body results from Summerheat Injury (Shangshu)." This is because cold damages the form (body structure) but not the Qi, hence the vigorous pulse; heat damages the Qi but not the form, hence the deficient pulse. (This distinguishes summerheat and heat, noting differences between sudden acquisition and latent qi, resulting in different pulse characteristics of fullness and deficiency.) Both summerheat and wind strike result in a deficient pulse, with greasy facial complexion, spontaneous sweating, irritability, and thirst. When static, heat damaging the Heart and Spleen constitutes summerheat stroke, which resembles summer heat disease; however, heat disease presents with a surging and tight pulse, while summerheat stroke presents with a fine, rapid, and deep pulse. When active, heat damaging the Taiyang meridian constitutes Zhong Yue (a type of summerheat stroke), with a floating pulse resembling summer wind strike; however, sweating and aversion to wind with fever but no thirst indicate wind strike, whereas fever with thirst indicates Zhong Yue. (What later generations call summerheat stroke often refers to Yin syndromes in summer.) There are four syndromes in summer: Cold Damage and Wind Strike, where pulses and symptoms intermingle; summerheat stroke and heat disease, which are similar and hard to distinguish. If the pulse is tight with aversion to cold, it is Cold Damage; if the pulse is slow with aversion to wind, it is Wind Strike; if the pulse is vigorous with high fever, it is heat disease; if the pulse is deficient with body heat, it is summerheat injury. These distinctions apply.
In the first or second day of heat disease, diarrhea, abdominal fullness, and severe heat indicate death.
In the third or fourth day, blurred vision, delirium, severe heat, and a small pulse indicate death.
In the fifth or sixth day, a scorched black tongue root and dry thirst indicate death.
In the seventh or eighth day, epistaxis, hematemesis, hematochezia, dry heat, and a large pulse indicate death.
In the ninth or tenth day, spasms accompanied by coma indicate death.
Regarding heat disease pulses, Cu (Hasty), Jie (Knotted), Fu (Deep/Hidden), Chen (Deep), and Xiao (Small) pulses are all difficult to treat. Heat disease without sweating and with a restless pulse is also difficult to treat. If sweating occurs but the heat intensifies and the pulse becomes restless, it indicates death.