误降之说，谓其麻未出透，降之太早，见他气急便实，无汗
昏睡，目赤眼开便可服之。如误服酸涩热补之剂，不可救药矣。
误降重表有钩藤，大力蝉衣复花同，
薄荷苏子甜桔梗，大青龙汤合剂攻。
解毒汤∶
自古黄连名解毒，黄柏黄芩共合成。
鼻红弄舌，牙有鲜血者，须用石膏、栀子、笋根，能清脾胃之热，再加茅根煎汁。如便血、吐血不止
者，解毒汤中加犀角、鲜地黄。烦渴作泻者，猪苓汤加黄连、花粉、石膏。干呕者，解
毒汤。呕不止者，陈皮、竹茹、石膏。下痢不止者，黄连、猪苓、泽泻、滑石、甘草。或滞后重，黄芩、
枳壳、木通、桔梗、升麻、叭杏、六一散与栝蒌仁。疹后气急咳嗽，连声不绝者，加
栝蒌仁、苏子、桑皮、枳壳、桔梗、麦冬，最用葶苈、冬花极妙，如若喘重者，麦冬清肺饮为宜。
清肺饮∶
清肺饮中又二冬，甘桔石膏杏仁同，
二母要求大力子，兜铃加上肺气通。
后壮热不退，发为搐搦，烦躁不宁，此心脾不宁也，宜四物汤加山栀、麦冬、甘草、木通，或下安神丸。
疹后虚烦不得眠，竹叶石膏汤加陈皮、麦冬。
疹后毒瓦斯攻内，循衣摸床，谵语神昏，丧珠者死。
疹后泻久不止，而变惊风者死。
疹后咳嗽连声不绝，而口哑者死。
疹见发不透而颈项肿硬者死。
疹见牙疳肿烂，唇齿肉落者死。
疹没后下痢不食，兼赤白口噤者死。
疹回后壮热，昼夜不退，身瘦弱者死。此因初起失表，毒火不能尽出，急宜表药与解毒治之。
疹出四五日不收者，内有热毒，清利治之，则热自解，疹已消回后，禁忌风寒湿水，否则必致咳嗽不休。
四十九日内余毒未除，肺虚咳嗽，下汗如雨，头汗如蒸，全身浮肿，宜用此方∶麦冬、冬花、知母、
橘红、百合、百部、阿胶（面粉炒）、沙参、贝母、钩藤、枇杷叶、榧子、兜铃、栝蒌仁。
疹若回后，如见发热，每渴用绿豆、芝麻炒米和煎茶饮，切
不可饮寒水，更宜生津解热而止渴，或用白虎汤代之亦可。
疹后二十日之后，其毒不解，邪火拂郁，浑身发热，昼夜不
退，发枯肌燥，渐成疳瘵，宜清热除疳丸主之。
清热除疳丸∶
清热除疳又黄连，归芎胆草陈干蟾，
发枯肤痒成疳瘵，加上君子治五疳，
再加笋荟共为末，神曲糊丸米汤下。
如浑身壮热未至瘦弱，但每烦躁搐搦不宁，此热在于心肝二经，以当归养血汤、黄连安神，间而服之。
当归养血汤∶
后壮热每烦躁，定知心脾有火熬，
四物汤中除芍药，安神养血须医早，
枇杷麦冬栀子入，灯竹木通甘草高，
假如气结连声嗽，桔梗蒌仁不可少，
天门麦冬入口消，知母枳壳天花炒，
若似气急耸肩嗽，血退场门鼻面色焦，
若非泻肺终难治，二冬二母与甘草，
桔梗杏仁与葶苈，兜铃糯米带甘草。
疹后咳嗽气喘，连声不住，此乃毒瓦斯流于肺，肺叶焦而动也。如胸前凸起，龟背直从而喘急，血出鼻
掀，握手摆头，面青色或白枯者，皆不治之症，如胸前不动用麦冬清肺饮治之。
疹后牙疳红肿者，宜服清胃饮。
升麻（二钱） 川连（一钱） 丹皮（二钱） 生地（二钱） 胃烂加生知母（二钱） 生石膏（三两） 清胃
饮合加荆芥（一钱） 大力（二钱） 玄参（二钱） 生甘草（一钱） 桔梗（二钱），疹回后杂症，或前或后，稍为
加减酌用。
关于“误降”的说法，是指麻疹尚未透发完全，就过早使用了泻下法，见到患儿气息急促、大便干结、无汗、昏睡、眼睛发红且睁开等症状时，便错误地使用了攻下药物。如果误服了酸涩收敛或温热补益的药物，那就无法救治了。
治疗因误用泻下法导致表邪未解的方剂包含钩藤、牛蒡子、蝉蜕和金银花，配合薄荷、苏子、甜桔梗，与大青龙汤合用以攻逐邪气。
解毒汤：
自古以来黄连被称为解毒良药，与黄柏、黄芩共同配伍而成。
若出现鼻孔出血、弄舌（伸吐舌头）、牙龈有鲜血的情况，必须使用石膏、栀子、芦根，以清除脾胃的热邪，再加入白茅根煎汁服用。如果出现便血、吐血不止的情况，在解毒汤中加入犀角、鲜地黄。如果烦躁口渴并伴有腹泻，使用猪苓汤加入黄连、天花粉、石膏。如果干呕，使用解毒汤。如果呕吐不止，使用陈皮、竹茹、石膏。如果痢疾不止，使用黄连、猪苓、泽泻、滑石、甘草。如果痢疾后期伴有里急后重，使用黄芩、枳壳、木通、桔梗、升麻、杏仁、六一散和瓜蒌仁。出疹后气息急促、咳嗽连声不绝的，加入瓜蒌仁、苏子、桑白皮、枳壳、桔梗、麦冬，特别推荐使用葶苈子和款冬花，效果极佳；如果喘息严重，使用麦冬清肺饮为宜。
麦冬清肺饮：
麦冬清肺饮中有天冬和麦冬，加上甘草、桔梗、石膏、杏仁，
还需要知母和贝母以及牛蒡子，加上紫菀则肺气通畅。
出疹后壮热不退，引发抽搐痉挛，烦躁不安，这是心脾不宁的表现，适宜使用四物汤加入山栀、麦冬、甘草、木通，或者服用安神丸。
出疹后虚烦不得入睡，使用竹叶石膏汤加入陈皮、麦冬。
出疹后毒邪内攻，出现循衣摸床（手指无意识地在衣被上抓摸）、胡言乱语、神志昏迷，瞳孔散大者死亡。
出疹后腹泻日久不止，进而变为惊风者死亡。
出疹后咳嗽连声不绝，进而口哑者死亡。
出疹时发出不透，且颈项肿硬者死亡。
出疹时出现牙疳（牙龈腐烂），嘴唇牙齿肌肉脱落者死亡。
疹退之后下痢不能进食，兼有赤白痢疾且口噤不开者死亡。
疹回之后壮热，昼夜不退，身体消瘦虚弱者死亡。这是因为初起时失于发表，毒火不能完全透出，急需使用发表药和解毒药治疗。
出疹四五日后皮疹不消退的，说明内有热毒，通过清热利湿治疗，热邪自解。疹子消退后，禁忌风寒湿水，否则必然导致咳嗽不止。
出疹后四十九天内余毒未除，肺虚咳嗽，全身出汗如雨，头部出汗如蒸，全身浮肿，适宜使用此方：麦冬、款冬花、知母、橘红、百合、百部、阿胶（面粉炒制）、沙参、贝母、钩藤、枇杷叶、榧子、紫菀、瓜蒌仁。
疹子消退后，如果再次发热，经常口渴，可用绿豆、芝麻、炒米一起煎煮代茶饮，切记不可饮用冷水，更宜生津解热止渴，或者用白虎汤替代也可以。
出疹二十日之后，毒邪未解，邪火拂郁，浑身发热，昼夜不退，头发枯槁肌肤干燥，逐渐形成疳瘵（慢性消耗性疾病），适宜用清热除疳丸主治。
清热除疳丸：
清热除疳丸中又有黄连，当归、川芎、胆草、陈皮、干蟾，
头发枯槁皮肤瘙痒形成疳瘵，加上使君子治疗五种疳积，
再加上芦荟共研为末，用神曲糊制成丸剂，米汤送服。
如果浑身壮热但尚未至消瘦虚弱，只是经常烦躁抽搐不安，这是热邪在心肝二经，可以交替服用当归养血汤和黄连安神丸。
当归养血汤：
出疹后壮热经常烦躁，定知心脾有火煎熬，
四物汤中去除芍药，安神养血须要医生尽早诊治，
加入枇杷叶、麦冬、山栀、灯心草、木通、甘草，
假如气结导致连声咳嗽，桔梗、瓜蒌仁不可缺少，
天门冬、麦冬入口即消，知母、枳壳、天花粉炒制，
如果像气急耸肩咳嗽，血退去后肛门及面色焦黑，
如果不是泻肺终难治愈，用天冬、麦冬、知母、贝母和甘草，
桔梗、杏仁和葶苈子，紫菀、糯米带甘草。
出疹后咳嗽气喘，连声不住，这是毒邪流注于肺，导致肺叶焦枯而动的表现。如果胸前凸起，龟背挺直且喘急，鼻孔出血掀动，握手摆头，面色青或苍白干枯的，都是不治之症；如果胸前不动，使用麦冬清肺饮治疗。
出疹后牙疳红肿的，适宜服用清胃饮。
升麻（二钱） 川黄连（一钱） 丹皮（二钱） 生地（二钱） 胃烂加生知母（二钱） 生石膏（三两） 清胃饮合加荆芥（一钱） 牛蒡子（二钱） 玄参（二钱） 生甘草（一钱） 桔梗（二钱），出疹后杂症，或在前或在后，稍微加减酌情使用。
Regarding the concept of "mistaken purgation" (Wu Jiang), it refers to the situation where measles have not fully erupted, yet purgatives are used too early. When symptoms such as rapid breathing, constipation, absence of sweat, lethargy, red and open eyes appear, one might mistakenly administer downward-draining medications. If astringent, sour, or hot tonic agents are mistakenly taken, the condition becomes incurable.
The formula for treating exterior syndrome caused by mistaken purgation includes Uncariae Ramulus cum Uncis (Gouteng), Arctii Fructus (Niubangzi), Periostracum Cicadae (Chanyi), and Flos Lonicerae Japonicae (Jinyinhua), combined with Menthae Haplocalycis Herba (Bohe), Perillae Fructus (Suzi), and sweet Platycodonis Radix (Tian Jiegeng), administered together with Dayqinglong Decoction to attack the pathogen.
Jiedu Tang (Detoxification Decoction):
Since ancient times, Coptidis Rhizoma (Huanglian) has been famous for detoxification, compounded together with Phellodendri Cortex (Huangbai) and Scutellariae Radix (Huangqin).
If nasal bleeding, tongue protrusion, or fresh blood in the gums occurs, Shigao (Gypsum Fibrosum), Zhizi (Gardeniae Fructus), and Genus Zizaniae Caulis (Sun Gen) must be used to clear heat from the Spleen and Stomach, plus decocted juice from Bai Ma Gen (Imperatae Rhizoma). If hematochezia or hematemesis persists, add Xijiao (Rhinocerotis Cornu) and Sheng Dihuang (Rehmanniae Radix Recens) to Jiedu Tang. If irritability, thirst, and diarrhea occur, use Zhuling Tang (Polypori Decoction) added with Huanglian, Huafen (Trichosanthis Radix), and Shigao. For dry retching, use Jiedu Tang. If vomiting persists, use Chenpi (Citri Reticulatae Pericarpium), Zhuru (Bambusae Caulis in Taenia), and Shigao. For persistent dysentery, use Huanglian, Zhuling, Zexie (Alismatis Rhizoma), Huashi (Talcum), and Gancao (Glycyrrhizae Radix et Rhizoma). If late-stage dysentery presents with tenesmus, use Huangqin, Zhike (Aurantii Fructus Immaturus), Mutong (Akebiae Caulis), Jiegeng (Platycodonis Radix), Shengma (Cimicifugae Rhizoma), Baxing (Prunus Armeniacae Semen), Liuyisan (Six-in-One Powder), and Gualouren (Trichosanthis Semen). For post-measles rapid breathing and incessant coughing, add Gualouren, Suzi, Sangbaipi (Mori Cortex), Zhike, Jiegeng, and Maidong (Ophiopogonis Radix); Tinglizi (Semen Lepidii et Descurainiae) and Donghua (Spiraeae Flos) are particularly excellent; if asthma is severe, Maidong Qingfei Yin (Ophiopogon Lung-Clearing Decoction) is appropriate.
Maidong Qingfei Yin:
Maidong Qingfei Yin contains both Tian Dong (Asparagi Radix) and Maidong, along with Gancao, Jiegeng, Shigao, and Xingren (Armeniacae Semen Amarum);
For Er Mu (Zhimu and Chuanbeimu) and Niubangzi, adding Douloung (Spiraeae Flos) unblocks Lung Qi.
Post-measles high fever that does not subside, leading to convulsions and restlessness, indicates Disharmony of Heart and Spleen; Siwu Tang (Four Substances Decoction) added with Zhizi, Maidong, Gancao, and Mutong, or Anshen Wan (Calming Spirit Pill) is suitable.
Post-measles deficiency-heat causing insomnia requires Zhuye Shigao Tang (Bamboo Leaf and Gypsum Decoction) added with Chenpi and Maidong.
Post-measles toxin attacking internally, manifesting as picking at clothes and bedclothes, delirium, and coma with dilated pupils, results in death.
Post-measles chronic diarrhea turning into infantile convulsion results in death.
Post-measles incessant cough turning into aphonia results in death.
Measles failing to erupt fully accompanied by stiff neck swelling results in death.
Measles presenting with noma (gangrenous stomatitis) and flesh falling from lips and teeth results in death.
Post-measles dysentery with anorexia, combined with bloody-white stools and trismus results in death.
Post-measles high fever persisting day and night with emaciation results in death. This is due to failure to release the exterior at onset, preventing complete expulsion of toxic fire; urgent treatment with exterior-releasing and detoxifying herbs is required.
If measles do not resolve after four to five days, internal toxic heat exists; clearing and draining will resolve the heat. After rash subsides, avoid wind, cold, dampness, and cold water, otherwise cough will persist indefinitely.
Within forty-nine days post-measles, if residual toxins remain, causing Lung deficiency cough, profuse sweating like rain, head sweating like steam, and generalized edema, use this formula: Maidong, Donghua, Zhimu (Anemarrhenae Rhizoma), Juhong (Citri Reticulatae Pericarpium Rubrum), Baihe (Lilii Bulbus), Baibu (Stemonae Radix), Ejiao (Colla Corii Asini fried with flour), Shashen (Glehniae Radix), Beimu (Fritillariae Bulbus), Gouteng, Pipaye (Eriobotryae Folium), Feizi (Torreya Seed), Douloung, and Gualouren.
After rash subsides, if fever returns with frequent thirst, decoct Mung Bean (Vigna Radiata), Sesame, and roasted rice for tea; strictly avoid cold water. Generating fluids, clearing heat, and stopping thirst is preferred; alternatively, Baihu Tang (White Tiger Decoction) may be substituted.
Twenty days post-measles, if toxins are unresolved, evil fire stagnates, causing whole-body fever persisting day and night, with hair becoming brittle and skin dry, gradually developing into gan zhai (chronic consumption disease), Qingre Chu Gan Wan (Heat-Clearing and Parasite-Expelling Pill) is indicated.
Qingre Chu Gan Wan:
Qingre Chu Gan Wan contains Huanglian, Danggui (Angelicae Sinensis Radix), Xiong (Chuanxiong Rhizoma), Dancao (Scutellariae Radix), Chenpi, and Gan Chan (Dry Bufo);
For brittle hair, itchy skin, and gan zhai, add Shijunzi (Quisqualis Fructus) to treat five types of parasitic accumulation;
Add Lvhui (Aloe) and grind into powder, form pills with Shenqu (Medicated Leaven), and swallow with rice soup.
If whole-body high fever exists without emaciation, but with frequent restlessness and convulsions, the heat is in the Heart and Liver meridians; alternate administration of Danggui Yangxue Tang (Danggui Blood-Nourishing Decoction) and Huanglian Anshen Wan (Coptis Calming Spirit Pill) is recommended.
Danggui Yangxue Tang:
Post-measles high fever and frequent restlessness indicate Fire boiling in Heart and Spleen;
In Siwu Tang, remove Shaoyao (Paeoniae Radix Alba); calming spirit and nourishing blood requires early medical intervention;
Add Pipaye, Maidong, Zhizi, Dengcaozhong (Centaurii Herba), Mutong, and Gancao;
If Qi stagnation causes incessant cough, Jiegeng and Gualouren are indispensable;
Tianmendong (Asparagi Radix) and Maidong soothe the throat; Zhimu, Zhike, and Tianhuafen (Trichosanthis Radix) stir-fried;
If resembling Qi urgency with shoulder shrugging cough, after blood retreats, anus and face become scorched;
Unless lungs are purged, cure is difficult; use Tian Dong, Maidong, Zhimu, Beimu, and Gancao;
Jiegeng, Xingren, and Tinglizi, along with Douloung, Nuomi (Oryza Sativa Germ), and Gancao.
Post-measles cough and asthma with incessant sound indicate toxin flowing into the Lung, causing Lung lobes to become scorched and move. If the chest protrudes, back is straight like a tortoise shell with rapid breathing, nose bleeds with flaring nostrils, hands clasp and head shakes, or face is cyanotic or pale and withered, these are untreatable conditions; if the chest remains immobile, treat with Maidong Qingfei Yin.
Post-measles swollen and red gums require Qingwei Yin (Stomach-Clearing Decoction).
Shengma (two qian), Chuanlian (one qian), Danpi (two qian), Shengdi (two qian); for rotten stomach add Sheng Zhimu (two qian) and raw Shigao (three liang);
Qingwei Yin combined with Jingjie (Schizonepetae Herba) (one qian), Nili (Niubangzi) (two qian), Xuanshen (Scrophulariae Radix), raw Gancao (one qian), and Jiegeng (two qian). For miscellaneous post-measles syndromes, whether before or after, adjust slightly according to circumstances.