天地六淫之气感人，多致发热，但手足稍微冷，恶寒而无汗，面色青惨不舒，左颊
有青纹者，伤寒之热也。手足稍微冷，发热有汗，面赤而光者，伤风之热也。目胞肿，右
颊有筋，发热时头额肚腹更甚，或兼呕吐腹疼者，伤食之热也。面色青红，额正中有纹，
手掌心有汗，时作惊惕，手络微动而发热者，惊热也。身热而倍能食，唇红颊赤，大小便
秘，胁下汗者，火热也。面色红黄，发热多汗，腹痛吐泻，暑邪湿热也。凡此症各不同，
而热则一。麻疹之热，又何以别？大法以面赤耳冷，手中指独冷，目含泪，鼻清涕，咳
嗽喷嚏为别耳。且麻疹发热见点，近者五六日，远则七八朝，甚者有十余日，不限定日
数也。初起一二日内，不可即行汗解，妄用寒凉，若热发微和，发一日退一日，可不必
服药。如热来连日不退，嗽烦无汗，宣毒发表汤主之，或用升麻葛根汤发之。
疹由胎毒，亦必因时令之气而发，先宜表托，使毒尽达于肌表。若过用寒凉，遏伏
热毒，则必不能出透，多致毒瓦斯内攻，喘闷而亡。若已出透，又当清利，以解余热，免
致疹后变生诸症。且疹属阳，热重则阴分受伤，血为所耗，故没后必须养血，以保阴亏
发燥，勿执泥于清利也。若病者血气和平，素无他疾，虽感时气，而正能胜邪，发热必然
和缓，微微汗出，神清气爽，二便调匀，见
点则透彻，收没亦不疾不徐，此为轻而易治，故万氏家法，戒用药不可太早，恐致耗散元
气，反生害患，必待见点方用，徐徐升发。然饮药亦有次第，凡一剂分作十余次服，以疹
在皮肤之间。若作一次服，则药性催之太速，每致谵语烦躁，是可为轻视妄药之良箴也。若
素有风寒食滞，表里交杂，一触邪阳，火旺之气，内外合发，而正不能制邪，必大热无
汗，躁烦口渴，神气不清，便闭尿涩，见点不能透彻，收散或太急速，则为重而难治，急
宜临机审察，果犯何逆，损其有余，扶其不足，毋稍存游移之见，此又万氏之法不可拘
守也。善治者机圆而法活，用药必合时宜，如时值温暖，宜发之以辛凉，用防风解毒汤。时
值暄热，宜治之以辛寒，用黄连解毒汤。若大寒之时，宜以辛温发之，用桂枝解毒汤，或
麻黄汤。当乍寒乍暖之际，宜以辛平发之，用升麻解毒汤，或荆防败毒散。因时用药，毋
伐天和，又须看人之虚实。如大便闭结，躁烦热重，疹发不出，属实症者，将酒蒸大黄
微利之。如大小便清利，热不重，吐利不止，属虚症者，可加人参、白术之类补托之。毋
实实，毋虚虚，贵得其平，中病则止。如用前药发散，一剂而疹仍不出，再作一剂，水
煎温服，外擦以芫荽酒，又以苎麻蘸酒戛之，务使肌理疏通，疹尽透发于表，庶无腹胀喘
闭之患。若再不出，则为不治之症矣。然亦有不尽然者，当人人束手之时，细心详察。
一初起发热，遍身自汗，此毒从汗解，麻疹易出。若自汗过多，又是火盛内迫，致汗
妄流，恐有亡阳之变，宜当归六黄汤加浮麦止之。
一发热鼻血，亦毒从鼻衄解也，不可妄治，倘血出太多，是火盛致血妄行，以茅花
汤主之。
一发热呕吐者，是邪火内逼，毒瓦斯上行，用竹茹石膏汤，微吐者不必用此。
一初起自利甚者，亦火邪内炽，毒瓦斯奔下大肠，宜升麻泽泻汤。
一初热里急后重，毒甚而滞下也，宜黄芩芍药汤。
一初热咳嗽气急，而出不快者，宜麻黄汤，春夏秋加石膏，冬加桂枝，或用羌活散，
或用消毒饮，外以芫荽酒自头至足遍擦之。
天地间的六淫邪气侵犯人体，大多会导致发热。但如果手足稍微发冷，怕冷且无汗，面色青暗不舒展，左脸颊有青色纹路的是伤寒引起的发热。如果手足稍微发冷，发热且有汗，面色红赤而有光泽的是伤风引起的发热。如果眼睑肿胀，右脸颊有筋脉显露，发热时头、额、肚腹症状更重，或者兼有呕吐腹痛的是伤食引起的发热。如果面色青红相间，额头正中有纹路，手掌心有汗，时常出现惊悸惕动，手络微动而发热的是惊热。如果身体发热且食欲倍增，嘴唇红、脸颊赤，大小便不通畅，胁下有汗的是火热证。如果面色红黄，发热多汗，腹痛吐泻，是暑邪湿热所致。以上各种病症各不相同，但都有发热的表现。麻疹的发热又该如何辨别呢？大致的原则是以面赤耳冷、手中指单独发冷、眼睛含泪、流清鼻涕、咳嗽喷嚏作为辨别的依据。而且麻疹从发热到出疹点显现，近的需五六天，远的需七八天，严重的甚至十余天，并不限定固定的天数。在初起的一两天内，不可立即使用发汗解表的方法，也不要乱用寒凉药物。如果热度轻微和缓，每天退一点，可以不必服药。如果热度连续几天不退，伴有咳嗽烦躁且无汗，应以宣毒发表汤为主治疗，或者使用升麻葛根汤来发散透疹。
疹子源于胎毒，但也必须因应时令之气才会发作，初期宜用表托法，使毒气完全达于肌表。如果过度使用寒凉药物，遏制伏留热毒，则必然不能透发出来，多导致毒瓦斯内攻，出现喘闷而死亡。如果疹子已经透发完毕，又应当使用清利之法，以解除余热，避免疹后产生其他变症。而且疹子属于阳证，热势重则会损伤阴分，血液被耗伤，所以在疹子消退后必须养血，以保护阴液亏损导致的燥象，不要固执地拘泥于清利之法。如果患者气血平和，素来没有其它疾病，虽然感受时气，但正气能战胜邪气，发热必然和缓，微微出汗，神志清爽，二便调匀，出疹点透彻，收没也不快不慢，这属于轻症且容易治疗。所以万氏家法告诫用药不可太早，恐怕耗散元气，反而生出祸患，一定要等到见点（出疹）时才使用，徐徐升发透疹。然而服药也有次序，凡是一剂药分成十几次服用，因为疹子在皮肤之间。如果一次服完，药性催促得太快，往往导致谵语烦躁，这可以作为轻视妄用药物者的良好箴言。如果素来有风寒食滞，表里夹杂，一旦触动邪阳火旺之气，内外合发，而正气不能制约邪气，必然大热无汗，躁烦口渴，神气不清，大便闭结小便涩滞，出疹不能透彻，收散或太快，这就属于重症且难治。此时急宜临机审察，究竟犯了什么逆证，损其有余，扶其不足，不要存有任何犹豫之见，这又是万氏之法不可拘泥守旧的地方。善于治病的人圆机活法，用药必合时宜。如正值温暖时节，宜用辛凉发散，用防风解毒汤。正值暄热时节，宜用辛寒治疗，用黄连解毒汤。若在大寒之时，宜用辛温发散，用桂枝解毒汤，或麻黄汤。当乍寒乍暖之际，宜用辛平发散，用升麻解毒汤，或荆防败毒散。因时用药，不要破坏天和之气，还必须看人的虚实情况。如大便闭结，躁烦热重，疹发不出，属实证的，将酒蒸大黄轻微通利它。如大小便清利，热不重，吐利不止，属虚证的，可加人参、白术之类补益托毒。不要实其实，不要虚其虚，贵在得其平衡，中病即止。如使用前药发散，一剂后疹仍不出，再作一剂，水煎温服，外用芫荽酒擦拭，又以苎麻蘸酒戛擦身体，务必使肌理疏通，疹尽透发于表，这样才没有腹胀喘闭的祸患。如果仍然不出，就是不治之症了。然而也有不尽然的情况，应当在人人束手无策之时，细心详察。
其一，初起发热，遍身自汗，这是毒气从汗而解，麻疹易出。如果自汗过多，又是火盛内迫，导致汗液妄流，恐怕有亡阳的变化，宜用当归六黄汤加浮小麦来止汗。
其二，发热鼻血，也是毒气从鼻衄而解，不可妄治，倘若出血太多，是火盛导致血液妄行，以茅花汤为主治疗。
其三，发热呕吐，是邪火内逼，毒瓦斯上行，用竹茹石膏汤，轻微呕吐的不必用此方。
其四，初起腹泻严重的，也是火邪内炽，毒瓦斯奔注大肠，宜用升麻泽泻汤。
其五，初热里急后重，毒甚而痢下，宜用黄芩芍药汤。
其六，初热咳嗽气急，而出疹不快的，宜用麻黄汤，春夏秋加石膏，冬加桂枝，或者用羌活散，或者用消毒饮，外用芫荽酒从头至足遍擦。
The six excesses (Liu Yin, 六淫) of the heaven and earth invade the human body, mostly causing fever. However, if the hands and feet are slightly cold, there is aversion to cold and no sweating, the complexion is dark blue and uncomfortable, and there are blue streaks on the left cheek, this is heat from Cold Damage (Shanghan, 伤寒). If the hands and feet are slightly cold, there is fever with sweating, and the face is red and lustrous, this is heat from Wind Injury (Shangfeng, 伤风). If the eyelids are swollen, there are visible tendons on the right cheek, symptoms in the head, forehead, abdomen, and belly are worse during fever, or accompanied by vomiting and abdominal pain, this is heat from Food Stagnation (Shangshi, 伤食). If the complexion is mixed blue and red, there are streaks in the center of the forehead, there is sweat on the palms, frequent startles and terrors occur, the hand collaterals move slightly while feverish, this is Heat from Fright (Jingre, 惊热). If the body is hot and appetite is significantly increased, lips are red, cheeks are flushed, stool and urine are constipated, and there is sweat under the hypochondrium, this is Fire Heat (Huore, 火热). If the complexion is red and yellow, fever is accompanied by profuse sweating, abdominal pain, vomiting, and diarrhea, this is caused by Summerheat-Dampness (Shuxie Shire, 暑邪湿热). All these syndromes differ, yet they all involve heat. How then should the heat of Measles (Mazhen, 麻疹) be distinguished? The general principle is to distinguish it by a red face and cold ears, the middle finger of the hand being uniquely cold, eyes containing tears, clear nasal discharge, coughing, and sneezing. Furthermore, from the onset of fever to the appearance of macules, it takes five to six days for those close, seven to eight days for those distant, and severe cases may take over ten days; the number of days is not fixed. In the first one or two days of onset, diaphoresis and resolution should not be performed immediately, nor should cold-cooling medicines be used recklessly. If the heat is mild and harmonious, receding day by day, medication may not be necessary. If the heat persists for consecutive days without abating, accompanied by cough, irritability, and anhidrosis, Xuan Du Fa Biao Tang (Toxin-Releasing Surface-Expelling Decoction) should be administered as the primary treatment, or Sheng Ma Ge Gen Tang (Ephedra and Pueraria Decoction) can be used to induce eruption.
Measles stem from fetal toxin but must also erupt due to seasonal qi. Initially, surface-expelling and supporting methods should be used to allow the toxin to fully reach the skin surface. If cold-cooling medicines are overused, suppressing and trapping the heat-toxin, eruption will inevitably fail to penetrate thoroughly, often leading to internal attack by toxin qi, resulting in panting, oppression, and death. Once the rash has fully erupted, clearing and draining methods should be employed to resolve residual heat, preventing various post-measles complications. Since measles belong to Yang, severe heat damages the Yin aspect, consuming blood; therefore, after the rash subsides, nourishing blood is essential to preserve Yin deficiency-induced dryness, rather than rigidly adhering to clearing and draining methods. If the patient's Qi and Blood are balanced and free of other diseases, although affected by seasonal pathogens, righteous Qi can overcome evil Qi. Fever will be mild, with slight sweating, clear spirit, and regular bowel and bladder movements. Eruption will be thorough, and subsidence neither too fast nor too slow. This constitutes a mild and easily treatable case. Thus, the Wan family method warns against using medicine too early, fearing it might dissipate Yuan Qi (Original Qi, 元气) and cause harm; medication should only be used once macules appear, promoting gradual eruption. However, administration requires order: one dose should be divided into more than ten servings because the rash resides in the skin. Taking it all at once accelerates drug action too rapidly, often causing delirium and irritability; this serves as a good admonition against reckless medication. If there is pre-existing Cold-Wind or Food Stagnation, mixing interior and exterior, triggering Evil Yang and vigorous Fire Qi, causing internal and external simultaneous eruption where Righteous Qi cannot control Evil Qi, there will be high fever, anhidrosis, restlessness, thirst, unclear spirit, constipation, and dysuria. Eruption will be unthorough, and subsidence may be too rapid. This is a severe and difficult case requiring immediate clinical assessment to identify the deviation, reduce excess, support deficiency, without hesitation. This illustrates that the Wan family method should not be rigidly followed. A skilled practitioner uses flexible methods appropriate to the time. During warm weather, acrid-cool diaphoresis is suitable, using Fang Feng Jie Du Tang (Saposhnikovia Detoxification Decoction). During hot weather, acrid-cold treatment is suitable, using Huang Lian Jie Du Tang (Coptis Detoxification Decoction). During severe cold, acrid-warm diaphoresis is suitable, using Gui Zhi Jie Du Tang (Cinnamon Twig Detoxification Decoction) or Ma Huang Tang (Ephedra Decoction). During fluctuating cold and warmth, acrid-neutral diaphoresis is suitable, using Sheng Ma Jie Du Tang (Cimicifuga Detoxification Decoction) or Jing Fang Bai Du San (Schizonepeta and Saposhnikovia Resolving Toxin Powder). Medication should follow the season without violating Heavenly Harmony, and must consider the patient's deficiency or excess. For constipation, restlessness, heavy heat, and failed eruption indicating Excess Syndrome, wine-steamed Da Huang (Rhubarb Rhizome) can be used for mild purgation. For clear bowel/bladder, light heat, continuous vomiting/diarrhea indicating Deficiency Syndrome, Ren Shen (Ginseng Root) and Bai Zhu (Atractylodes Rhizome) can be added to tonify and support. Do not reinforce excess or further weaken deficiency; aim for balance, stopping when the disease is addressed. If prior diaphoretic agents fail to produce eruption after one dose, prepare another dose, decoct in water, and take warm. Externally, apply Yan Xu (Coriander Fruit) wine, and rub with Ramie dipped in wine, ensuring skin pores open and rash erupts fully to avoid abdominal distension and panting obstruction. If still no eruption, it is incurable. However, exceptions exist; careful observation is needed when others give up.
First, initial fever with generalized spontaneous sweating indicates toxin release via sweat, making measles easy to erupt. Excessive sweating suggests excessive Fire forcing fluids out, risking Yang collapse; use Dang Gui Liu Huang Tang (Angelica Six-Huang Decoction) plus Fu Mai (Floating Wheat) to stop sweating.
Second, fever with epistaxis also indicates toxin release via nosebleed; do not treat recklessly. If bleeding is excessive due to Fire forcing blood to flow wildly, use Mao Hua Tang (Thistle Flower Decoction).
Third, fever with vomiting indicates Evil Fire forcing toxin upward; use Zhu Ru Shi Gao Tang (Bamboo Shavings and Gypsum Decoction). Mild vomiting does not require this.
Fourth, severe initial diarrhea indicates intense internal Fire and toxin rushing to the Large Intestine; use Sheng Ma Ze Xie Tang (Cimicifuga and Alisma Decoction).
Fifth, initial heat with tenesmus indicates severe toxin and dysentery; use Huang Qin Shao Yao Tang (Scutellaria and Peony Decoction).
Sixth, initial heat with cough, rapid breathing, and slow eruption: use Ma Huang Tang (Ephedra Decoction), adding Shi Gao (Gypsum Fibrosum) in Spring/Summer/Autumn, Gui Zhi (Cinnamon Twig) in Winter, or Qiang Huo San (Notopterygium Powder), or Xiao Du Yin (Detoxification Drink). Externally, wipe from head to toe with Yan Xu (Coriander Fruit) wine.