杨如侯曰∶伏火感冒一证，近来盛行，人每认识不清，多致轻转重，重转危。此证古人未有另立明条，而混于伤寒
温热之类，是以后人往往误治，今不得不重申其义。秋燥之气，由呼吸吸入肺中，传于血脉，火毒内蕴，流行血中。一
入冬令，大气寒肃，将火毒遏抑于内。血脉为寒束缚，以致汗血管闭，血度高升，则寒热交作，头晕或痛，口苦舌燥，
胸满身痛。人多不察，动用羌、柴、芷、葛、细辛、荆、防辛燥风药，风煽火势，益增烈炎。故热血火毒，逼迫妄行，
速度愈加，变证百出，以致皮肤微焦，血管破裂，为痧斑疹 喉痹等危险之证。轻者屡月不瘥，重者便成不起。
杨如侯曰∶冬温脉寸洪尺数，或实大，心烦、呕逆、身热、不恶寒，或头痛、身重、面肿、咳嗽、咽痛、下利，此
冬感非节之暖而病温也。冬温发热而微畏寒，汗不出而烦扰，此冬先感温气，即被严寒遏抑而病温也。按第一条谓冬时
有非节之暖，未至而至，即为不正之气，独冬不藏精之人，肾气先泄，腠理不固，温气袭人，感之而病；第二条谓先感
温气，即被严寒遏抑而病者，此因暴冷折阳，表有寒邪，故有微恶寒之见证，与上条但发热者不同。此皆属于冬温，表
邪若涉一二，里热必兼八九，斯瘾疹、丹痧相继而作矣。况冬月兼有伏暑、伏燥之证，不得以时在冬月，认作伤寒，遽
以麻、桂、羌、柴、荆、防之属，鼓风煽火，而增其烈炎之焰也。
周禹载曰∶冬温与春温无异，而时令不同。
叶天士曰∶入冬以来，暴冷折阳，外感发热头痛、身痛呕恶，必从太阳。若渴能饮水，即是里热见证，不得纯以表
散。
又曰∶若冬令应寒，气候温暖，阳气不潜，当藏反泄，即能致病，名曰冬温。
陆九芝曰∶冬月病热，即是冬温，不可用正伤寒之桂、麻，则亦有须用膏、栀、芩、连者。
雷少逸曰∶昔贤谓冬应寒而反温，非其时而有其气，人感之而即病者，名曰冬温是也。其劳力辛苦之人，动作汗出，
温气乘袭，多在于表；其冬不藏精之人，肾经不足，温气乘袭，多在于里。冬温虽发于冬时，然用药之法，与伤寒迥别。
盖温则气泄，寒则气敛，二气本属相反，误用辛温，变证叠出矣。其证头痛有汗，咳嗽口渴，不恶寒而恶热，或面浮，
或咽痛，或胸疼，阳脉浮滑有力者，乃温邪窜入肺经也，宜用辛凉解表法，加连翘、象贝治之。口渴甚者，温邪入胃腑
也，再加芦根、花粉治之。如或下利，阴脉不浮而滑，温邪已陷于里也，宜以清凉透邪法，加葛根、黄芩治之。倘热势
转剧，神气昏愦，谵语错乱，舌苔转黑者，不易治也，勉以祛热宣窍法治之，紫雪丹亦可用之。种种变证，不能尽述，
须仿诸温门中之法可也。
又或问曰∶冬温发热而不恶寒，倘恶寒者，为何病也？答曰∶冬温恶寒，偶亦有之，良由先感温气，即被严寒所侵，
寒在外而温在里，宜用辛温解表法，先去寒邪，继用凉解里热法，而清温气。又问曰∶伤寒、冒寒皆恶寒，何以别之？
曰∶伤寒、冒寒，初起无口渴，以此别之。曰∶温邪当发为冬温，倘其微者，伏而不发，为何病也？曰∶伏而不发，来
春必变为温毒也。凡治时病者，新邪伏气，切要分明，庶不至千里毫厘之失。
陈莲舫曰∶冬温乃属新感，伏而不发，来春必成温毒。
杨如侯说：伏火感冒这一证候，近来非常盛行，人们往往认识不清，导致轻症转为重症，重症转为危症。这种证候古人在医书中没有单独设立明确的条文，而是混杂在伤寒和温热的论述中，因此后人常常误治，现在不得不重新阐述其义理。秋季的燥气，通过呼吸吸入肺中，传入血脉，火毒内蕴，在血液中流行。一到冬季，大气寒冷肃杀，将火毒遏制压抑在体内。血脉被寒气束缚，导致汗毛孔闭塞，血压升高，于是出现寒热交替发作、头晕或头痛、口苦舌燥、胸闷全身疼痛等症状。人们大多不仔细考察，就使用羌活、柴胡、白芷、葛根、细辛、荆芥、防风等辛燥的风药，风势煽动火势，更加增加了烈火的燃烧。因此热血和火毒逼迫血液妄行，速度加快，变证百出，以致皮肤微微焦枯，血管破裂，出现痧斑、疹子、喉痹等危险的证候。轻的几个月不能痊愈，重的就会死亡。
杨如侯说：冬温病的脉象是寸部洪大、尺部数急，或者脉实而大，症状有心烦、呕吐逆气、身体发热、不怕冷，或者有头痛、身体沉重、面部浮肿、咳嗽、咽喉痛、腹泻，这是冬天感受了不合时节的温暖之气而患的温病。冬温发热且轻微怕冷，无汗且烦躁不安，这是因为冬天先感受了温气，随即被严寒遏制压抑而患的温病。按第一条所说，冬天有不合时节的温暖，未到时节却提前到来，这就是不正之气，只有那些冬天不能藏精的人，肾气先泄，腠理不坚固，温气侵袭人体，感之而发病；第二条所说先感受温气，随即被严寒遏制压抑而发病的，这是因为暴冷的天气折损阳气，体表有寒邪，所以有轻微恶寒的表现，与上一条只发热的情况不同。这些都属于冬温，表邪如果占一二成，里热必然兼有八九成，这样瘾疹、丹痧就会相继发作。况且冬季兼有伏暑、伏燥的证候，不能因为时间在冬季，就认为是伤寒，匆忙使用麻黄、桂枝、羌活、柴胡、荆芥、防风之类的药物，鼓动风势煽动火势，从而增加烈火的火焰啊。
叶天士说：入冬以来，暴冷的天气折损阳气，外感发热、头痛、身痛、呕吐恶心，病邪必定从太阳经开始。如果口渴能饮水，就是里热的表现，不能单纯用解表发散的方法。
又说：如果冬天应当寒冷，气候却温暖，阳气不能潜藏，应当收藏反而泄露，就能致病，名叫冬温。
陆九芝说：冬天得热病，就是冬温，不能用治疗正伤寒的桂枝、麻黄，但也会有需要用石膏、栀子、黄芩、黄连的情况。
雷少逸说：以前的贤人说冬天应当寒冷却反而温暖，不是那个时节却有那个气候，人感受它就立即发病的，名叫冬温。那些从事体力劳动辛苦的人，动作出汗，温气乘虚侵袭，病位多在体表；那些冬天不能藏精的人，肾经不足，温气乘虚侵袭，病位多在体内。冬温虽然发于冬季，但是用药的方法，与伤寒截然不同。大概温热则气机发泄，寒冷则气机收敛，这两种气本来属于相反的性质，误用辛温的药物，变证就会接连出现。其症状表现为头痛有汗、咳嗽口渴、不怕冷反而怕热，或者面部浮肿，或者咽喉痛，或者胸痛，阳脉浮滑有力的，是温邪窜入肺经，适宜用辛凉解表法，加连翘、象贝母治疗。口渴严重的，是温邪进入胃腑，再加芦根、天花粉治疗。如果出现腹泻，阴脉不浮而滑，说明温邪已经陷入体内，适宜用清凉透邪法，加葛根、黄芩治疗。如果热势转剧，神志昏沉迷糊，说胡话错乱，舌苔转黑的，就不容易治疗了，勉强用祛热宣窍法治它，紫雪丹也可以使用。各种变证，不能全部叙述，必须仿效各类温病门中的方法即可。
又有人问：冬温发热而不怕冷，如果有怕冷的，是什么病呢？回答说：冬温也有偶尔怕冷的，这大多是因为先感受温气，随即被严寒所侵，寒在体表而温在体内，适宜用辛温解表法，先去寒邪，继用凉解里热法，来清解温气。又问：伤寒、冒寒都怕冷，怎么区别它们呢？回答说：伤寒、冒寒，初起时没有口渴，以此作为区别。问：温邪应当发为冬温，如果轻微的，潜伏而不发作，是什么病呢？回答说：潜伏而不发作，来年春天一定会变为温毒。凡是治疗时令病的，新感邪气和伏气温邪，一定要分辨清楚，才不至于造成千里之差的失误。
Yang Ruhou stated: The syndrome of "latent fire cold" (Fuhuo Ganmao) has recently become prevalent. People often fail to recognize it clearly, leading to mild cases becoming severe and severe cases becoming critical. This syndrome was not explicitly defined in ancient texts but was mixed with discussions on Cold Damage (Shanghan) and Warm Diseases (Wenre), causing later generations to often treat it incorrectly. Therefore, its principles must be reiterated. The dryness qi of autumn is inhaled through respiration into the lungs, transmitted into the blood vessels, where fire toxins accumulate and circulate within the blood. Upon entering winter, the atmospheric cold becomes stern, suppressing the fire toxins inside. Constrained by the cold, the blood vessels tighten, sweat pores close, and blood pressure rises, resulting in alternating chills and fever, dizziness or headache, bitter taste in the mouth, dry tongue, chest fullness, and body pain. People often fail to examine this carefully and instead use acrid-dry wind-dispelling herbs such as Qianghuo (Notopterygii Rhizoma et Radix), Chaihu (Bupleuri Radix), Baizhi (Angelicae Dahuricae Radix), Gegen (Puerariae Lobatae Radix), Xixin (Asari Radix et Rhizoma), Jingjie (Schizonepetae Herba), and Fangfeng (Saposhnikoviae Radix). The wind fans the fire, further intensifying the flames. Consequently, hot blood and fire toxins force abnormal circulation, accelerating the process and producing myriad complications. This leads to slightly scorched skin, ruptured blood vessels, and dangerous conditions such as sand spots (Shaban), rashes (Zhen), and throat bi (Houbi). Mild cases may last for months without healing, while severe cases may result in death.
Yang Ruhou stated: In Winter-Warmth (Dongwen), the pulse is surging at the Cun position and rapid at the Chi position, or solid and large. Symptoms include restlessness, vomiting and regurgitation, fever, aversion to cold absent, headache, heaviness of the body, facial edema, cough, sore throat, and diarrhea. This occurs when one contracts warmth due to unseasonably warm weather in winter. When Winter-Warmth presents with fever and slight aversion to cold, absence of sweating, and irritability, it is because the person first contracted warm qi and was then suppressed by severe cold. According to the first description, unseasonable warmth arriving before its time constitutes an aberrant qi. Only those who failed to store essence during winter have depleted Kidney qi and insecure interstices (Couli); thus, warm qi attacks them, causing disease. According to the second description, contracting warm qi and then being suppressed by severe cold results from sudden cold damaging Yang, leaving cold pathogenic factors on the exterior, hence the slight aversion to cold, which differs from the first case involving only fever. These all belong to Winter-Warmth. If exterior pathogenic factors account for one or two parts, interior heat must account for eight or nine parts, leading to successive outbreaks of macules (Yinzhen) and scarlet fever-like rashes (Dansha). Moreover, since latent summerheat (Fushu) and latent dryness (Fuzao) coexist in winter, one must not assume it is Cold Damage merely because it is winter, nor hastily use herbs like Mahuang (Ephedrae Herba), Guizhi (Cinnamomi Ramulus), Qianghuo, Chaihu, Jingjie, and Fangfeng to stir wind and fan fire, thereby increasing the intensity of the flames.
Zhou Yuzai stated: Winter-Warmth is no different from Spring-Warmth, differing only in the seasonal timing.
Ye Tianshi stated: Since entering winter, sudden cold has damaged Yang. Exogenous febrile diseases presenting with fever, headache, body pain, vomiting, and nausea must originate from the Taiyang (Greater Yang) channel. If there is thirst and desire to drink water, this indicates interior heat; pure exterior-releasing methods should not be used.
He also stated: If winter should be cold but the climate is warm, causing Yang qi to fail to submerge and leaking when it should be stored, disease will occur, named Winter-Warmth.
Lu Jiuzhi stated: Febrile diseases occurring in winter are Winter-Warmth. Zheng-Sanghan (Standard Cold Damage) formulas containing Guizhi and Mahuang should not be used. However, there are cases requiring Shigao (Gypsum Fibrosum), Zhizi (Gardeniae Fructus), Huangqin (Scutellariae Radix), and Lian (Coptidis Rhizoma).
Lei Shaoyi stated: Ancient sages said that when winter should be cold but is instead warm, possessing the climate out of season, and people contract it immediately falling ill, this is called Winter-Warmth. For those engaged in hard physical labor who sweat during exertion, warm qi attacks the exterior. For those who failed to store essence in winter and have insufficient Kidney meridian qi, warm qi attacks the interior. Although Winter-Warmth manifests in winter, its treatment method is radically different from Cold Damage. Warmth causes qi to dissipate, while cold causes qi to converge; these two natures are opposite. Misusing acrid-warm herbs leads to successive complications. Symptoms include headache with sweating, cough, thirst, aversion to heat rather than cold, facial edema, sore throat, or chest pain. If the Yang pulses are floating, slippery, and forceful, it indicates warm pathogens invading the Lung meridian; acrid-cool exterior-releasing methods should be used, adding Qiaofiao (Forsythiae Fructus) and Xiangbei (Fritillariae Thunbergii Bulbus). If thirst is severe, warm pathogens have entered the Stomach fu organ; add Lugeng (Phragmitis Rhizoma) and Huafen (Trichosanthis Radix). If diarrhea occurs and Yin pulses are floating-less but slippery, warm pathogens have sunk into the interior; cool-clearing and pathogen-extruding methods should be used, adding Gegen and Huangqin. If heat worsens significantly, consciousness becomes confused, delirium occurs, and the tongue coating turns black, the condition is difficult to treat. One may attempt heat-removing and orifice-opening methods; Zixue Dan (Purple Snow Pill) can also be used. Various complications cannot be fully listed; one must emulate methods from various Warm Disease categories.
Another question was asked: Winter-Warmth presents with fever and no aversion to cold. If there is aversion to cold, what disease is it? The answer is: Aversion to cold in Winter-Warmth occasionally occurs, usually because warm qi was first contracted and then invaded by severe cold. Cold is on the exterior and warmth is in the interior. Acrid-warm exterior-releasing methods should be used first to dispel cold pathogens, followed by cool-clearing interior-heat methods to clear the warm qi. Another question: Both Cold Damage (Shanghan) and Cold Exposure (Maohan) present with aversion to cold. How to distinguish them? Answer: Cold Damage and Cold Exposure have no thirst in the initial stage; this distinguishes them. Question: If warm pathogens develop into Winter-Warmth, but if mild ones lie latent and do not manifest, what disease is it? Answer: Latent and unmanifested, they will transform into Warm Toxin (Wendu) in the following spring. In treating seasonal diseases, new exogenous pathogens and latent qi must be clearly distinguished to avoid significant errors.
Chen Lianfang stated: Winter-Warmth belongs to new contraction. If it lies latent and does not manifest, it will certainly become Warm Toxin in the following spring.