夫痘成斑烂之症有二。凡当发散而不发散，则毒内壅于胸膈而乃喘促闷乱，毒瓦斯奔
溃皮肤，则成此疾。其不当发散而强发散，则腠理洞开，阳气暴泄，热毒尽发肌表，亦
成此疾，治宜保脾土，和荣胃，则毒瓦斯自解，湿烂自收也。更有未周小儿，疮虽红
活，但稠密无缝，则血气不能充任，亦成斑烂，是谓小船不堪重载，必致沉覆也。若乳
食能进，禁处全无，颜色润泽，咽喉清亮而不肿痛，及无他疾攻害者，间有保全。更有
发表过甚，以致外斑烂而肉中虚，阳气不守，脏腑自利，此又急当救里，宜木香散主
之，甚至厥逆者，异攻散可也。
夫痘所贵者，坚实不破，圆净成痂也。其有溃烂者，是火胜也。《经》曰∶热胜则
肉败，盖火之为用，猛虐峻暴，近之则燥痒不宁，迫之则焦痛难忍，灼之则糜烂成疮，
故败物者，莫如火也。然火生于空，非虚不燃，乘之以风，其炎益烈，故痘溃烂者，由
肌肉素虚，邪风侵袭，风者，善行数变，是以行诸脉俞，而散于荣卫之间，一旦毒发于
里，则风应于表，风火相扇，肌肉愤 ，皮肤决裂而疮坏矣。如脓成而溃者，则毒已
化，但虑其粘衣渍席，不能收较耳。外用败草散衬之，丹溪所谓，疮湿者，须去湿，内
服风药，白芷防风之类，或利小便也。若脓浆未成，其毒未化，痒破溃烂者，则卫气暴
泄，津液不荣，譬如草木剥削其皮，则枯萎
而死矣。《经》曰∶根于中者，命曰神机，神去则机息。根于外者，命曰气立，气止则
化绝者，此之谓也。若靥后复溃者，乃余毒失于解利，留滞于肌肉之间也，治宜解毒渗
湿。若痘烂无脓，吐利不止，或二便下血，乳食不化者，并皆不治。
痘疮演变为斑烂的病症有两种情况。凡是应当使用发散法治疗却未进行发散，导致毒邪在胸膈内部壅滞，从而出现气喘急促、胸闷烦乱；或者毒气奔涌溃破皮肤，就会形成这种疾病。对于不应当使用发散法而强行发散的情况，会导致腠理（皮肤毛孔及纹理）大开，阳气突然外泄，热毒全部发于肌表，也会形成这种疾病。治疗适宜保护脾土，调和营卫与胃气，那么毒气自然解除，湿烂之症自然收敛。还有未满周岁的婴儿，虽然痘疮颜色红活，但分布稠密无缝隙，导致血气无法充盈承载，也会形成斑烂，这好比小船不堪重载，必然导致沉没覆灭。如果乳食能够进食，患处完全没有其他禁忌症状，色泽润泽，咽喉清亮且不肿痛，也没有其他疾病侵害的，偶尔有保全生机的。还有因为发表（发散解表）过度，导致外部斑烂而肌肉内部空虚，阳气不能固守，脏腑自行下利，这种情况又急需救里，适宜用木香散主治，甚至出现四肢厥冷的，可以用异攻散。
痘疮最可贵的是坚实不破，圆满干净结成痂皮。那些出现溃烂的，是火邪亢盛所致。《内经》说：热邪胜则肌肉败坏。大概火的功用，猛烈暴虐，靠近它则干燥瘙痒不安，逼迫它则焦痛难忍，灼烧它则糜烂成疮，所以败坏事物的，没有比得上火的了。然而火生于虚空之中，不是虚弱就不会燃烧，乘着风势，火势更加猛烈，所以痘疮溃烂，是因为肌肉素来虚弱，邪风侵袭。风邪善于运行且变化多端，因此行走在各经脉俞穴之间，散布在荣卫之间，一旦毒邪发于体内，风邪就应合于体表，风火相互煽动，肌肉肿胀突起，皮肤破裂而疮疡毁坏。如果脓液形成而后溃破，说明毒邪已经化解，只是担心脓水粘衣浸席，难以收口罢了。外用败草散铺垫，丹溪所说，疮疡潮湿者，必须祛湿，内服风药，如白芷、防风之类，或者通利小便。如果脓浆未形成，毒邪未化解，因痒抓破而溃烂的，则是卫气突然外泄，津液不能滋养肌肤，好比草木剥落了树皮，就会枯萎而死。《内经》说：根源于体内的，叫做神机，神气离去则机能停止。根源于体外的，叫做气立，气止息则化生断绝，说的就是这种情况。如果在结痂后再次溃烂的，是余毒未能彻底解除，留滞在肌肉之间，治疗适宜解毒渗湿。如果痘疮溃烂无脓，呕吐腹泻不止，或者大小便下血，乳食不消化的，都属于不治之症。
There are two types of cases where smallpox develops into maceration (skin erosion and ulceration). First, if the condition requires dispersing methods but they are not applied, the pathogenic toxin becomes stagnant within the chest and diaphragm, leading to panting, shortness of breath, and mental restlessness; or if the toxic qi rushes and breaks through the skin, this disease results. Second, if dispersing methods are forcibly applied when inappropriate, the couli (pores and interstices) open widely, causing a sudden leakage of Yang Qi, with heat toxins fully manifesting on the muscle surface, also resulting in this disease. Treatment should focus on protecting Spleen Earth and harmonizing Ying (Nutritive) Qi and Stomach Qi, so that the toxic qi will naturally resolve and the wet erosions will heal. Additionally, in infants under one year old, although the lesions may appear red and vibrant, if they are densely packed without gaps, the Blood and Qi cannot adequately support them, leading to maceration. This is likened to a small boat unable to bear a heavy load, inevitably sinking. If the infant can take milk and food, there are no contraindicated symptoms at the lesion sites, the complexion is lustrous, the throat is clear without swelling or pain, and no other diseases are attacking, survival is occasionally possible. Furthermore, if excessive dispersing leads to external maceration while the muscles become empty internally, and Yang Qi fails to remain secure, causing spontaneous diarrhea from the Zang-Fu organs, this situation urgently requires rescuing the interior. Muxiang San (Aucklandia Powder) is indicated, and for severe cases with cold limbs (Jue Ni), Yigong San (Yi Gong Powder) may be used.
The most desirable outcome for smallpox is that it remains firm, does not break, and forms round, clean scabs. Cases involving ulceration indicate an excess of Fire. The Classic states: "When Heat prevails, flesh decays." The function of Fire is fierce and violent; proximity causes dryness and itching, pressure causes burning pain, and scorching leads to erosion and sores. Thus, nothing destroys matter like Fire. However, Fire arises from emptiness and does not burn unless there is deficiency. When driven by Wind, its flames intensify. Therefore, smallpox ulceration occurs because the muscles are inherently deficient, allowing Evil Wind to invade. Wind is agile and changeable, traveling through the meridians and acupoints, and scattering between Ying and Wei (Defensive) Qi. Once the toxin erupts from the interior, Wind responds on the exterior. Wind and Fire fan each other, causing the muscles to swell and the skin to rupture, leading to the destruction of the sores. If pus forms and then ulcerates, the toxin has transformed; the only concern is that the discharge may stick to clothes and bedding, hindering healing. Externally, Baicao San (Decayed Grass Powder) can be used as a dressing. As Danxi stated, for damp sores, dampness must be removed; internally, Wind-dispersing herbs such as Bai Zhi (Angelicae Dahuricae Radix) and Fang Feng (Saposhnikoviae Radix) may be used, or diuretics to promote urination. If the pus has not formed and the toxin has not transformed, and scratching due to itching causes ulceration, the Wei Qi has suddenly leaked, and body fluids fail to nourish the tissues. This is like trees losing their bark, leading to withering and death. The Classic states: "Those rooted within are called Shen Ji (Spirit Mechanism); when Spirit departs, mechanism ceases. Those rooted externally are called Qi Li (Qi Establishment); when Qi stops, transformation ends." This refers to the aforementioned situation. If ulceration recurs after crusting, it is due to residual toxins failing to be cleared, remaining stagnant in the muscles. Treatment should focus on resolving toxicity and leaching out dampness. If smallpox ulcers have no pus, accompanied by incessant vomiting and diarrhea, blood in stool or urine, and inability to digest milk and food, these are all incurable.