疹喜清凉而恶湿，痘喜温暖而恶凉，此固其大法也。然亦当有得其宜者，如疹子初出亦
须和暖则易出，所以发苗之初只要发出得尽，则疹毒便解。非若痘之苗而秀，秀而实，而后
毒解也。痘疮成熟之时，若太温热则反溃烂不收，是痘之后亦喜清凉也。故治痘疹者无过
热，无过寒，必温凉适宜，使阴阳和平，是为得之。
痘宜内实可用补剂，疹忌内实只惟解散。惟初热发表时略相似耳，既出之后痘宜补气，
以生血，疹宜养阴，以制阳，何也？盖疹热甚则阴分受其熬煎，而血多虚耗，阴金被克，故治
以清火滋阴为主，而不可少动其气，若燥悍之剂，首尾皆深忌也。世知痘证所系之重，而不
知疹之杀人尤烈，方书多忽而不备，良可太息也夫。
斑疹之毒皆由于火，《内经》曰∶赫曦之纪，其病疮疡。故或遇二火司天，或司运之岁，
肺金受制，感而发者居多。轻者如蚊迹之状，或垒肿于皮肤间，名曰瘾疹。重者如珠点红
晕，或片片如锦纹，名曰斑疹。大抵色赤者吉，色黑者凶，其证似伤寒发热，凡三四日而出，
七八日而靥也。凡此之类皆属邪热，治之之法惟辛凉解利而已。即若吐泻亦断不可用温补
也，如豆蔻干姜之类切勿轻用，而初发之时尤不可大汗，只宜升麻葛根透邪煎之属微表之
耳，故用宜斟酌，有不可一概取必也。
标出不红，现而发热转甚，或头痛，身痛烦躁者，升麻汤或透邪煎。
色赤稠密，身痛烦躁者，升麻汤加紫草连翘。
寒热并作，头痛背强者，升麻汤加羌活防风连翘。
头项面肿，升麻汤加牛蒡子荆芥；若脉强火盛热渴者，宜清降其火，以白虎汤加减用之。
自汗烦渴，气壅脉数者，化斑汤。
身热烦渴泄泻者，柴苓汤或四苓散，如夏月用益元散。
热甚，小便赤涩，谵语惊恐者，导赤散、四苓散加辰砂，夏月益元散加辰砂。
咳嗽甚者，二母散、麦门冬汤、清肺汤。
喘者小柴胡汤去人参加五味子。（德按∶痧疹初出究非虚喘，五味子切不可加）
热甚鼻衄，或便血、溺血热甚者，黄连解毒汤；血甚者，犀角地黄汤。
伤寒呕吐，六君子汤加藿香干葛，或减去人参；热甚呕吐者，解毒汤；小便不利而呕吐
者，四苓散；一二日不通者，导赤散。
大便秘结，发热身痛者，大柴胡汤；腹胀气喘者前胡枳壳汤。
咽喉不利甘桔汤，兼风热咳嗽者，加防风。
寒热往来似疟小柴胡汤，如兼咳嗽去人参。
靥后身热不除者，升麻汤；或去升麻加黄芩黄连各用酒炒。
下利赤白腹痛者，黄芩芍药汤，或加枳壳；身热腹痛者，解毒汤。
余毒未尽，变生痈疽疮疖者，升麻汤加荆芥防风牛蒡子连翘。
景岳曰∶按以上万氏治疹诸条皆极详明，然其中惟泻痢、气喘二证则最多疑似。盖二证
之由疹毒，因当如其治矣。然有不因疹毒者，如俗医但见是疹无不概用寒凉，不知有可凉
者，有不可凉者，其有脾气本弱而过用寒药，或以误食生冷致伤脾胃，而为泄泻者亦多有
之，此一证也。虽曰由疹而发，而实非疹毒之病矣，但察其别无热证热脉，而兼之色白气馁
者，便须速救脾肾，急从温补。若执谓疹毒不可温则无不危矣，此医之当知本也。又如气喘
一证，大有虚实，盖十喘九虚。若察其本非火证，又非外邪，而或以大泻，或以大汗而致喘
者，此皆气脱之后也。凡此二者皆不可不加细察，而或者以气促作气喘，则万万大误矣。又
痘疮总论中有因人因证之辨，与此麻疹实同一理，所当参阅，故不可以麻疹之邪悉认为实
火，而不知虚火之为害也。
徐氏东皋曰∶痘难疹易之说此俗谈耳，其有胃气原弱所感入深，又或因泻痢而发有不
快，或发之未透，而随现随隐，久之邪气渐入于胃，必泄泻不已，出而复出，加之喘促，则必
危矣。凡若此者又岂可以易言哉，所以但有出疹，若见虚弱急当先补脾胃，其有欲出不出，
急当托里发表以助之，且首尾俱不可泻，（言用下也）一如痘证同也。
疹子喜欢清凉而厌恶潮湿，痘疮喜欢温暖而厌恶寒冷，这固然是它们的基本治疗原则。然而，也应当根据具体情况适宜处理。例如，疹子在初出时也需要温和的环境才容易透发，所以在发疹初期只要能让疹毒完全发出，疹毒自然就会解除。这与痘疮不同，痘疮需要经过“苗”（起顶）、“秀”（灌浆）、“实”（结痂）的过程后，毒邪才能解除。当痘疮成熟时，如果环境过于温热反而会导致溃烂而不愈合，这说明痘疮后期也喜欢清凉。因此，治疗痘疮和疹子，既不能过热，也不能过寒，必须使温凉适宜，让阴阳达到平衡，这才是正确的治法。
痘疮适合体内充实，可以使用补剂；疹子忌讳体内充实，只宜使用解散透发的方法。只有在初期发热需要发表透疹时，两者的治法略有相似之处。疹子发出之后，痘疮宜补气以生血，疹子宜养阴以制约阳热，为什么呢？因为疹子热势猛烈，会煎熬阴分，导致血液大量虚耗，肺金（属金，对应肺）受到火克，所以治疗以清火滋阴为主，不可轻易扰动正气，像燥烈刚悍的药物，从头到尾都应当深为禁忌。世人只知道痘证关系重大，却不知道疹子致人死亡更为猛烈，医书中对此往往忽视而不详尽记载，实在令人叹息。
斑疹的毒邪都源于火，《黄帝内经》说：“赫曦之纪（火热旺盛的年份或气候），其病多为疮疡。”所以，如果遇到二火（少阴君火、少阳相火）司天，或者岁运为火之年，肺金受制，感受邪气而发病的情况居多。轻症的表现为像蚊子叮咬后的痕迹，或者在皮肤间垒起肿胀，名叫瘾疹。重症的表现像珍珠点样的红晕，或者成片如锦缎花纹，名叫斑疹。大体上，颜色赤红的预后较好，颜色黑紫的预后凶险。这些病症类似伤寒发热，通常在发病后三四天出疹，七八天结痂脱落。凡此种种都属于邪热，治疗方法只有辛凉解表利咽而已。即使是出现呕吐腹泻，也绝对不可使用温补药物，如豆蔻、干姜之类的药切勿轻易使用。而且在初发之时尤其不可大汗淋漓，只宜用升麻葛根透邪煎等具有轻微发汗作用的方剂，所以用药应当斟酌，不可一概而论。
若皮疹标出不红，显现后发热加重，或伴有头痛、身痛、烦躁的，用升麻汤或透邪煎。
若皮疹颜色赤红且稠密，伴有身痛、烦躁的，用升麻汤加紫草、连翘。
若恶寒发热同时发作，伴有头痛、项背强直的，用升麻汤加羌活、防风、连翘。
若头项面部肿胀，用升麻汤加牛蒡子、荆芥；若脉象强劲、火盛、口渴者，宜清降其火，用白虎汤加减服用。
若自汗、心烦口渴、气机壅滞、脉数者，用化斑汤。
若身热、心烦口渴、泄泻者，用柴苓汤或四苓散，如果是夏季则用益元散。
若热势甚重，小便赤涩，胡言乱语、惊恐者，用导赤散、四苓散加辰砂，夏季用益元散加辰砂。
若咳嗽严重者，用二母散、麦门冬汤、清肺汤。
若气喘者，用小柴胡汤去掉人参，加入五味子。（德按：痧疹初出终究不是虚喘，五味子切不可加入）
若热势甚重导致鼻出血，或便血、尿血且热势甚者，用黄连解毒汤；若出血严重者的，用犀角地黄汤。
若伤寒引起呕吐，用六君子汤加藿香、干葛，或者减去人参；若热势甚重引起呕吐的，用解毒汤；若小便不利且呕吐的，用四苓散；若一二日大便不通的，用导赤散。
若大便秘结，发热身痛的，用大柴胡汤；若腹胀气喘的，用前胡枳壳汤。
若咽喉不利，用甘桔汤，兼有风热咳嗽的，加防风。
若寒热往来似疟疾的，用小柴胡汤，如兼有咳嗽则去掉人参。
若结痂脱落后身热不退的，用升麻汤；或者去掉升麻，加入黄芩、黄连各用酒炒。
若下利赤白痢、腹痛的，用黄芩芍药汤，或者加枳壳；若身热腹痛的，用解毒汤。
若余毒未尽，变生痈疽疮疖的，用升麻汤加荆芥、防风、牛蒡子、连翘。
张景岳说：按照以上万氏治疗疹子的各种条文都非常详细明确，然而其中只有泻痢、气喘两个证候最容易产生疑惑。这两个证候如果是由于疹毒引起的，当然应当按照上述方法治疗。但是也有并非由疹毒引起的，比如庸俗的医生只见是疹子就一概使用寒凉药物，不知道有的可以凉，有的不可以凉。那些脾气本来虚弱而过用寒药，或者因误食生冷损伤脾胃而导致泄泻的也有很多，这是第一种情况。虽然说是由疹子引发，但实际上并不是疹毒的病证。只要观察没有其他热证热脉，并且兼见面色苍白、气息微弱的，就必须迅速救助脾肾，紧急采用温补之法。如果固执地认为疹毒不可温补，那么没有不危险的，这是医生应当知晓的根本道理。又如气喘这一证候，虚实差别很大，大概十次气喘中有九次是虚证。如果观察发现本非火证，也不是外邪，而是因为大泻或大汗导致气喘的，这都是气脱之后的表现。这两种情况都不可以不仔细察辨，而有些人把气促当作气喘，那就万万错误了。另外，在痘疮总论中有因人因证的辨别，与麻疹的道理相同，应当参考阅读，所以不可以把麻疹的邪气全部认为是实火，而不知道虚火的危害。
徐氏东皋说：“痘难疹易”的说法只是世俗的谈资罢了。那些胃气原本虚弱、感邪较深的人，又或因泻痢而发病不畅，或者疹子发出未透彻，随即出现随即隐没，久而久之邪气逐渐侵入胃中，必然导致泄泻不止，疹子出了又出，再加上气喘急促，那就必定危险了。凡是这种情况，又岂能说是容易呢？所以只要有出疹现象，如果见到虚弱，应当先补益脾胃；那些想要发出却发不出的，应当紧急托里发表以帮助透发，而且从头到尾都不可使用泻下法（指用攻下药），这一点与痘证是一样的。
Maoles (Rash) favor coolness and dislike dampness, while smallpox favors warmth and dislikes cold; this is indeed their general principle. However, treatment must also be appropriate to the specific situation. For instance, when maoles first appear, a warm environment is required for them to emerge easily. Therefore, in the initial stage of eruption, as long as the rash toxins are fully expelled, the toxins will naturally resolve. This differs from smallpox, where the toxin resolves only after progressing through the stages of "bud" (papule), "flower" (vesicle/pustule), and "fruit" (crust). When smallpox matures, if it is too warm, it may instead become ulcerated and fail to heal, indicating that smallpox also favors coolness in its later stages. Thus, in treating both smallpox and maoles, one must avoid excessive heat and excessive cold, ensuring a balance of warmth and coolness so that Yin and Yang achieve harmony; this constitutes correct treatment.
Smallpox benefits from internal fullness and can use tonifying formulas; maoles contraindicate internal fullness and require only dispersing and resolving methods. Their approaches are only slightly similar during the initial fever stage when releasing the exterior. After eruption, smallpox should be treated by tonifying Qi to generate Blood, whereas maoles should be treated by nourishing Yin to restrain Yang. Why? Because intense heat from maoles boils the Yin aspect, leading to significant depletion of Blood, and Fire overacts on Metal (Lung). Therefore, treatment focuses primarily on clearing Heat and nourishing Yin, without disturbing Qi. Harsh and drying agents are deeply contraindicated from beginning to end. The world recognizes the severity of smallpox but fails to realize that maoles are even more lethal; medical texts often neglect this, which is truly lamentable.
The toxins of macules and rashes all originate from Fire. The *Neijing* states: "In the era of He Xi (intense heat), diseases manifest as sores and ulcers." Thus, when Shaoyin Ministerial Fire or Shaoyang Triple Burner Fire governs the year or season, or when the annual运气 (Yun) is Fire, Lung Metal is constrained, and most cases arise from pathogenic invasion. Mild cases present like mosquito bites or raised swellings in the skin, named *Yinzhen* (Urticaria/Hives). Severe cases present like red halos around pearl-like spots or patches resembling brocade patterns, named *Ban Zhen* (Macules and Papules/Rash). Generally, red color indicates a favorable prognosis, while black indicates an unfavorable one. These conditions resemble Typhoid Fever (Shanghan) with fever, typically erupting 3-4 days after onset and crusting over 7-8 days. All such cases belong to Pathogenic Heat; the treatment method is solely Acrid-Cool release and resolution. Even if vomiting and diarrhea occur, warm tonics must absolutely not be used; herbs like Cardamomi Fructus (Doukou) and Zingiberis Radix Preparata (Ganjiang) must never be lightly employed. During the initial eruption, profuse sweating is especially contraindicated; only mild diaphoretic formulas like Shengma Gegen Touxie Decoction should be used. Therefore, medication requires careful consideration and cannot be applied uniformly.
If the rash marks do not turn red, and fever worsens upon appearance, accompanied by headache, body pain, and irritability, use Shengma Tang or Touxie Jian.
If the rash is bright red and dense, accompanied by body pain and irritability, use Shengma Tang added with Arnebiae Radix seu Rhizoma (Zicao) and Forsythiae Fructus (Lianqiao).
If chills and fever occur simultaneously, accompanied by headache and stiffness of the neck and back, use Shengma Tang added with Notopterygii Rhizoma et Radix (Qianghuo), Saposhnikoviae Radix (Fangfeng), and Forsythiae Fructus (Lianqiao).
If there is swelling of the head, neck, and face, use Shengma Tang added with Armeniacae Semen Amarum (Niubangzi) and Schizonepetae Spica (Jingjie); if the pulse is strong, Fire is abundant, and thirst exists, clear and descend the Fire using Baihu Tang modified.
If there is spontaneous sweating, irritability, thirst, Qi stagnation, and a rapid pulse, use Huaban Tang.
If there is fever, irritability, thirst, and diarrhea, use Chai Ling Tang or Siling San; in summer, use Yiyuan San.
If the heat is severe, urine is red and difficult to pass, and there is delirium and fright, use Daochi San and Siling San added with Cinnabar (Chensha); in summer, use Yiyuan San added with Cinnabar (Chensha).
If cough is severe, use Ermu San, Maimendong Tang, or Qingfei Tang.
If there is wheezing/asthma, use Xiaochaihu Tang with Ginseng removed and Schisandrae Fructus (Wuweizi) added. (Note: Rash eruption is fundamentally not deficiency-type asthma; Wuweizi must absolutely not be added.)
If heat is severe causing epistaxis, hematochezia, or hematuria, use Huanglian Jiedu Tang; if bleeding is severe, use Xijiao Dihuang Tang.
If Shanghan causes vomiting, use Liujunzi Tang added with Agastachis Herba (Huoxiang) and Puerariae Radix (Gegen), or remove Ginseng; if heat causes vomiting, use Jiedu Tang; if urinary difficulty accompanies vomiting, use Siling San; if constipation persists for 1-2 days, use Daochi San.
If constipation, fever, and body pain exist, use Da Chaihu Tang; if abdominal distension and wheezing exist, use Qianhu Zhike Tang.
For throat discomfort, use Ganjie Tang; if accompanied by wind-heat cough, add Schizonepetae Spica (Jingjie).
For alternating chills and fever resembling malaria, use Xiaochaihu Tang; if accompanied by cough, remove Ginseng.
If fever persists after crusting falls off, use Shengma Tang; or remove Shengma and add Scutellariae Radix (Huangqin) and Coptidis Rhizoma (Huanglian), both stir-fried with wine.
For dysentery with red and white stool and abdominal pain, use Huangqin Shaoyao Tang, or add Zhiqi; for fever and abdominal pain, use Jiedu Tang.
If residual toxins remain and transform into carbuncles, sores, or boils, use Shengma Tang added with Schizonepetae Spica (Jingjie), Notopterygii Rhizoma et Radix (Qianghuo), Armeniacae Semen Amarum (Niubangzi), and Forsythiae Fructus (Lianqiao).
Zhang Jingyue stated: Regarding Wan's various detailed treatments for rash above, the conditions of diarrhea/dysentery and wheezing/asthma are the most prone to confusion. If these conditions stem from rash toxins, they should be treated accordingly. However, some are not caused by rash toxins. For example, quack doctors see a rash and indiscriminately use cold-cooling herbs, not knowing that some can be cooled and others cannot. Patients with weak Spleen Qi who have overused cold herbs, or those injured by eating raw/cold foods causing diarrhea, are common. Although triggered by the rash, this is actually not a disease of rash toxin. If no other heat signs or pulses are present, and pallor and weak Qi are observed, one must quickly rescue the Spleen and Kidney with urgent warming and tonification. Insisting that rash toxins cannot be warmed leads to danger; this is the fundamental knowledge physicians must possess. Similarly, regarding wheezing/asthma, there is great difference between excess and deficiency; nine out of ten cases are deficiency. If it is determined not to be a Fire condition nor external pathogen, but caused by severe purging or sweating leading to wheezing, this represents Qi collapse. Both cases require careful differentiation. Mistaking shortness of breath for wheezing/asthma is a grave error. Furthermore, the differentiation based on individual constitution and syndrome in the General Discussion of Smallpox applies equally to measles/rash; reference is advised. One must not assume all rash pathogens are Excess Fire, ignoring the harm of Deficiency Fire.
Xu Donggao stated: The saying "smallpox is difficult, rash is easy" is merely vulgar talk. In cases where Stomach Qi is originally weak, pathogenic invasion is deep, or eruption is hindered by diarrhea/dysentery, or the rash fails to fully emerge and repeatedly appears and disappears, pathogenic Qi gradually enters the Stomach, inevitably causing persistent diarrhea, recurrent eruption, and combined with wheezing/asthma, leading to critical danger. Such cases certainly cannot be called "easy." Therefore, whenever rash appears, if weakness is observed, tonify the Spleen and Stomach first. If the rash wants to emerge but cannot, urgently use interior-supporting and exterior-releasing methods to assist it. Purging (using downward-draining herbs) is contraindicated from start to finish, just as in smallpox treatment.