陈氏曰∶凡痘疮出不快者，多属于虚，若误谓实热壅盛，妄用宣利之药，致脏腑受冷，营卫涩
滞，不能运达肌肤，则不能起发充满，亦不能结实成痂，后必痒 ，烦躁喘渴而死。
薛氏曰∶前证亦有各经热盛，壅遏而出不快者，亦有毒盛痘疔而不能起发者，亦有余毒而溃痒
者，当细审其因而药之。
景岳曰∶接此二子之说，皆为有理，但此出迟不起之证，总是气血内虚不能速达者为最多，若
风寒外闭，及痘疔留毒而不出不起者，虽亦有之，但不多耳。再若各经热盛而壅遏不出者，则尤为
最少，何也？盖热盛者毒必盛，毒盛者势必疾速，而或密或早，无能缓也。故凡治此者，必当察其
热之微甚，以辨虚实，再察外邪之有无以辨表里。如无外邪，亦无痘疔而火邪不甚者，则尽属虚证，
宜从温补，不得杂乱以遗后患也。诸治法详报痘三朝治款中。
凡看痘之法，其出欲尽，出不尽者伏也；其发欲透，发不透者倒陷也；其收欲净，收不净者倒
靥也。伏唯一证，陷有数种。凡毒之伏者，患在未壮之先，其人疮虽出而热不少减，或烦渴，或躁
闷，此必有伏毒未得全出也。陷则患于既壮之后，其血渐干而变黑者，谓之黑陷；浆脓未成而为痒
，或破损者，谓之倒陷；浆脓既成而复湿烂，皮破不肯结靥，收不干净者，谓之倒靥，亦陷类也
，是皆恶候。凡治此者，使非猛峻之剂，安能望其回生。时医欲以寻常之药救此危病，其犹放雀搏
，驱羊敌虎耳。故其轻者宜夺命丹，重者宜神应夺命丹，则其庶几耳。倘服药后而反增黑色者，
为必不治之证。
一、痘之留伏毒不尽出者，证有不同，当辨治之。有元气不足而托送无力者，此必禀赋素弱，饮
食素少，身无大热而出有不透，即不足之证也，宜十宣散、蝉蜕膏之类，加独圣散主之，若虚而有
热者，宜人参透肌散。有毒盛气滞，留伏经络而出不透者，必其人气体浓浊，身有大热而汗不易出
，即皆有余之证，宜荆防败毒散主之。若表里俱实，外有大热，内有秘结烦满，而留伏不透者，宜
双解散。
一、干黑不起而倒陷者，当分五证∶一则内虚而阳气不能外达，故致出而复没，或斑点白色，或
见灰黑倒
陷者，必其人不能乳食，或腹胀内寒，或手足冷，或吐泻，或寒战咬于，皆内虚也，速宜温中，轻
则十宣散、六气煎；甚则陈氏十二味异功散，或九味异功煎；外用胡荽酒喷之，或更用十全大补汤
。但得冷者暖，陷者起，黑音红活，便是佳兆。若服药后而反加烦躁昏乱者死。二则毒瓦斯太盛，内
外熏灼，不能尽达于表，因而复陷于里，乃致热烦躁扰，气喘妄言，或大小便不利，渴而腹胀，是
皆毒瓦斯之倒陷也，轻者利小便，宜大连翘饮、通关散，或四顺清凉饮；甚者通大便，宜承气汤，并
外用水杨汤浴之。得利后疮出则佳，更用加味四圣散调治之。凡治此者，但得阳气不败，脾胃温暖
，身温欲饮水者生。苦加寒战身冷，汗出耳尻反热者死。三则外感风寒，肌窍闭塞，血脉不行，必
身痛，或四肢微厥，斑点不长，或变紫黑如瘾疹者，此倒伏也，宜温肌散表，用桂枝葛根汤加麻黄
、蝉蜕，或紫草饮，外用胡荽酒喷之，但令温散寒邪，使热气得行，则痘自长矣。四则或因误下，
毒瓦斯入里而黑陷者，先宜六气煎，或温胃饮以培养胃气。如表有未解者，后宜柴葛桂枝汤以疏散于
外，甚者再加麻黄。五则以房室不洁，或为秽恶所触而黑陷者，宜内服紫草饮子，外用胡荽酒喷之
，或用茵陈熏法，并用辟邪丹。
一、将起发时，虽有浆水，但色见黑黯者，最为可畏，急宜六气煎加川芍以香血气，血气旺则
毒自散而色自活矣。或以十全大补汤合无价散主之。
一、凡倒靥之证，亦须看大便何如，苦大便秘结而内热者宜利之，以四顺清凉饮，或三黄丸主
之。若大便不实而内不热者宜补之，以六气煎，或十全大补汤加防风、白芷；甚而泄泻者，宜陈氏
十二味异功散。有虽不泄泻而虚寒甚者，宜九味异功煎，并外用败草散。
一、治陷伏证有三验法，凡服药之后，但得陷者复肿，渐以成脓，乃一验也；苦原疮已干而别
于空处另出一层，起发成脓，渐以收靥者，二验也；亦有不肿不出，只变自利，下去脓血而饮食精神
如故者，三验也，有验者吉，无则凶。
陈氏说：凡是痘疮发出迟缓的，大多属于虚证。如果错误地认为是实热壅盛，妄用宣通泻下的药物，导致脏腑受寒，营卫气血涩滞，不能运行通达肌肤，那么痘疮就不能起发饱满，也不能结实结痂，最终必然因瘙痒、烦躁、气喘口渴而死亡。
薛氏说：上述病症也有各经热盛，壅遏阻滞而导致发出迟缓的；也有毒气旺盛形成痘疔而不能起发的；也有余毒未清导致溃烂瘙痒的，应当仔细审察病因然后用药治疗。
景岳（张介宾）说：综合这两位先生的说法，都有道理。但是这种发出迟缓和不起发的病症，绝大多数总是因为气血内部虚弱，不能迅速到达体表所致。如果是风寒外邪闭塞，以及痘疔留毒导致不出不起的情况，虽然也有，但并不多见。至于各经热盛壅遏导致不出的情况，则更为少见。为什么呢？因为热盛则毒必盛，毒盛则病势必然急骤，或者密集或者早出，没有能迟缓的。所以凡是治疗这种情况，必须观察热的程度轻重，以辨别虚实；再观察是否有外邪，以辨别表里。如果没有外邪，也没有痘疔，且火邪不严重的，则完全属于虚证，适宜采用温补法，不得杂乱用药以免留下后患。具体的治疗方法详见《痘疹三朝治款》中。
大凡观察痘疮的方法：痘疮发出希望尽透，发出不尽的称为“伏”；痘疮起发希望透彻，起发不透的称为“倒陷”；痘疮收靥希望干净，收得不干净的称为“倒靥”。“伏”只有一种证候，“陷”有多种类型。凡是毒气潜伏的，发生在痘疮尚未壮盛之前，患者痘疮虽然发出但热势并不稍减，或者烦渴，或者躁闷，这必定是有伏毒未能全部透出。陷入则发生在痘疮已经壮盛之后，其血液逐渐干枯变为黑色的，称为“黑陷”；浆脓尚未形成却出现瘙痒，或者破损的，称为“倒陷”；浆脓已经形成却又湿烂，皮肤破裂不肯结痂，收靥不干净的，称为“倒靥”，也属于陷类，这些都是恶候。凡是治疗这些病症，如果不是使用猛烈峻急的药物，怎么能期望起死回生呢？当时的医生想用寻常药物来救治这种危重疾病，这就像放飞麻雀去搏斗、驱赶羊群去对抗老虎一样徒劳。所以病情较轻的宜用夺命丹，病情较重的宜用神应夺命丹，这样或许还有一线生机。如果服药后反而增加黑色斑点的，是必定无法治愈的证候。
其一，痘疮留有伏毒未能尽出的，证候有所不同，应当辨证治疗。有元气不足而托送无力者，这必定是禀赋素来虚弱，饮食摄入少，身体没有大热但痘疮发出不透，这是不足的证候，适宜用十宣散、蝉蜕膏之类，加独圣散为主治疗；如果虚而有热的，适宜用人参透肌散。有毒气旺盛气机阻滞，留伏在经络导致发出不透的，必定是此人形体气息浓浊，身体有大热且汗不易出，这都是有余的证候，适宜用荆防败毒散为主治疗。如果表里俱实，外部有大热，内部有便秘烦满，且留伏不透的，适宜用双解散。
其一，干黑不起而倒陷的，应当分为五种证候：一是内虚而阳气不能外达，导致痘疮发出后又隐没，或者斑点呈白色，或者见灰黑倒陷的，必定是此人不能吃奶进食，或者腹胀内寒，或者手脚冰冷，或者呕吐腹泻，或者寒战咬牙，这都是内虚，速宜温中，轻症用十宣散、六气煎；重症用陈氏十二味异功散，或九味异功煎；外用胡荽酒喷洒，或者再用十全大补汤。只要能使冷的变暖，陷的起发，黑的变红活，就是佳兆。如果服药后反而加重烦躁昏乱的，预后不良致死。二是毒气太盛，内外熏灼，不能全部达于体表，因而又陷入体内，导致热烦躁扰，气喘胡言乱语，或者大小便不利，口渴腹胀，这都是毒气的倒陷，轻者利小便，宜用大连翘饮、通关散，或四顺清凉饮；重症通大便，宜用承气汤，并外用水杨汤沐浴。得利后痘疮发出则是佳兆，再用加味四圣散调治。凡是治疗这类病症，只要阳气不败，脾胃温暖，身体温和想喝水的就能生存。如果加上寒战身冷，出汗且耳朵和臀部反热的，预后不良致死。三是外感风寒，肌窍闭塞，血脉不行，必定身体疼痛，或者四肢微厥，斑点不长，或者变成紫黑如瘾疹的，这是倒伏，宜温肌解表，用桂枝葛根汤加麻黄、蝉蜕，或紫草饮，外用胡荽酒喷洒，只要令温散寒邪，使热气得以运行，则痘疮自然生长。四是因误用下法，毒气入里而黑陷的，先宜用六气煎，或温胃饮以培养胃气。如果表证未解的，后用柴葛桂枝汤以疏散于外，重症再加麻黄。五是因为房室不洁，或被秽恶之气触犯而黑陷的，宜内服紫草饮子，外用胡荽酒喷洒，或用茵陈熏法，并用辟邪丹。
其一，在即将起发时，虽然有浆水，但颜色呈现黑黯的，最为可怕，急宜用六气煎加川芎以行血气，血气旺盛则毒自散而颜色自然鲜活了。或者用十全大补汤合无价散为主治疗。
其一，凡是倒靥的证候，也必须看大便情况如何，如果大便秘结而内有热的宜通利，以四顺清凉饮，或三黄丸为主治疗。如果大便不成形而内无热的宜补益，以六气煎，或十全大补汤加防风、白芷；严重到泄泻的，宜用陈氏十二味异功散。有虽然不泄泻但虚寒很严重的，宜用九味异功煎，并外用败草散。
其一，治疗陷伏证有三种验证方法：凡是服药之后，只要得凹陷处重新肿胀，渐渐成脓，这是一验；如果原疮已干而在空处另出一层，起发成脓，渐渐收靥的，是二验；也有不肿不出，只变为自利（腹泻），下去脓血而饮食精神如常的，是三验。有验证迹象的为吉，没有则为凶。
Chen stated: Whenever smallpox eruptions are slow to appear, it mostly belongs to deficiency syndromes. If mistakenly considered as excess heat and toxin accumulation, and wrongly administered with purgative or draining medicines, it will cause the internal organs to suffer from cold, leading to stagnation of Ying (Nutritive) and Wei (Defensive) Qi, preventing them from circulating to the skin and muscles. Consequently, the eruptions cannot rise and fill out, nor can they solidify into scabs. Eventually, the patient will die from itching, restlessness, panting, and thirst.
Xue stated: The aforementioned conditions may also arise from excessive heat in various meridians, causing obstruction and slow eruption; or from severe toxins forming pustules that fail to rise; or from residual toxins causing ulceration and itching. One must carefully examine the etiology before prescribing medication.
Jingyue (Zhang Jiebin) stated: Both previous statements are reasonable. However, cases of delayed appearance and failure to rise are most commonly due to internal deficiency of Qi and Blood, which cannot reach the surface quickly. Cases caused by external closure of Wind-Cold, or toxins retained in pustules, do occur but are rare. Cases caused by excessive heat in various meridians obstructing eruption are even rarer. Why? Because when heat is excessive, the toxin must be severe; when the toxin is severe, the disease process tends to be rapid, appearing either densely or early, without delay. Therefore, in treating such cases, one must observe the degree of heat to differentiate between excess and deficiency, and check for the presence of external pathogens to differentiate between exterior and interior. If there are no external pathogens, no pustules, and the fire pathogen is not severe, it entirely belongs to deficiency syndromes, suitable for warming and tonifying methods. One must avoid杂乱 (mixed/disordered) treatments to prevent future complications. Detailed treatment methods are reported in the "Three Days of Smallpox Treatment" section.
In observing smallpox, the goal is for eruptions to appear completely; incomplete appearance is called "Fu" (Lagging/Trapped). The goal is for eruptions to rise thoroughly; incomplete rising is called "Dao Xian" (Inverse Collapse). The goal is for crusting to be clean; unclean crusting is called "Dao Ye" (Inverse Crusting). "Fu" has only one syndrome type, while "Xian" (Collapse) has several types. When toxins are trapped, it occurs before the eruptions become vigorous. Although eruptions appear, the fever does not decrease slightly, accompanied by irritability/thirst or restlessness/distress, indicating trapped toxins have not fully emerged. "Xian" occurs after the eruptions have become vigorous. If the blood dries up and turns black, it is called "Hei Xian" (Black Collapse); if pus fails to form yet itching occurs, or lesions break open, it is called "Dao Xian" (Inverse Collapse); if pus forms but becomes wet and rotting, skin breaks and refuses to crust over, resulting in unclean recovery, it is called "Dao Ye" (Inverse Crusting), which is also a type of collapse. These are all ominous signs. Treating these requires potent and drastic medicines; otherwise, revival is impossible. Contemporary physicians attempting to save such critical illnesses with ordinary medicines is like releasing sparrows to fight or driving sheep against tigers. For mild cases, Du Ming Dan (Life-Rescuing Pill) is appropriate; for severe cases, Shen Ying Duo Ming Dan (Divine Response Life-Rescuing Pill) is appropriate, offering a chance of survival. If black spots increase after taking medicine, it is an untreatable condition.
First, regarding smallpox with retained trapped toxins not fully emerging, syndromes vary and require differentiation. If Yuan Qi (Primal Qi) is insufficient and lacks strength to push toxins out, this indicates innate weakness and poor diet, presenting with no high fever but incomplete eruption, signifying deficiency. Shi Xuan San (Ten-Accumulation Powder) and Chan Tui Gao (Cicada Slough Paste), added with Du Sheng San (Single-Sage Powder), are indicated. If deficiency accompanies heat, Ren Shen Tou Ji San (Ginseng Penetrating-Muscle Powder) is indicated. If toxins are severe and Qi stagnation traps toxins in collaterals, preventing eruption, the patient typically has dense/turbid constitution, high fever, and difficulty sweating, indicating excess. Jing Fang Bai Du San (Schizonepeta and Saposhnikovia Decoction to Overcome Toxins) is indicated. If both exterior and interior are excess, with external high fever and internal constipation/restfulness, Shuang Jie San (Double-Release Powder) is indicated.
Second, regarding dry blackness, failure to rise, and inverse collapse, five syndromes should be distinguished:
1. Internal deficiency where Yang Qi cannot reach the exterior, causing eruptions to emerge then vanish, or white spots, or gray-black inverse collapse. The patient cannot nurse/eat, has abdominal distension/internal cold, cold hands/feet, vomiting/diarrhea, or chattering teeth. This is internal deficiency. Rapidly warm the middle. Mild cases: Shi Xuan San, Liu Qi Jian (Six-Qi Decoction). Severe cases: Chen's Twelve-Ingredient Yi Gong San (Extraordinary Function Powder) or Jiu Wei Yi Gong Jian (Nine-Ingredient Extraordinary Function Decoction). Externally spray Hu Su Jiu (Coriander Wine) or use Shi Quan Da Bu Tang (Complete Great Tonifying Decoction). If cold becomes warm, collapse rises, and black turns red/lively, it is a good omen. If restlessness/confusion worsens after medication, death ensues.
2. Toxin Qi is too severe, burning internally and externally, unable to reach the surface, thus sinking back inward. This causes heat, restlessness, panting, delirium, difficult urination/defecation, thirst, and abdominal distension. This is toxic inverse collapse. Mild cases: promote urination with Da Lian Qiao Yin (Large Forsythia Drink), Tong Guan San (Opening Pass Powder), or Si Shun Qing Liang Yin (Four-Compliance Cooling Clearing Drink). Severe cases: promote defecation with Cheng Qi Tang (Inherit the Qi Decoction), and externally bathe in Shui Yang Tang (Water Poplar Decoction). Good sign if eruptions appear after bowel movement, followed by Jia Wei Si Sheng San (Modified Four-Sages Powder). Survival depends on preserving Yang Qi, keeping Spleen/Stomach warm, body temperature normal, and desire for water. Death if accompanied by chills, cold body, sweating, and hot ears/buttocks.
3. External contraction of Wind-Cold, closing muscle pores, blocking blood vessels. Symptoms include body pain, slight cold limbs, spots failing to grow, or turning purple-black like hives. This is inverse trapping. Warm muscles and release the exterior using Gui Zhi Ge Gen Tang (Cinnamon Twig and Pueraria Decoction) added with Ma Huang (Ephedrae Herba) and Chan Tui (Cicada Slough), or Zi Cao Yin (Arnebia Drink). Externally spray Hu Su Jiu. Warming and dispersing Cold allows Heat Qi to circulate, and eruptions will grow naturally.
4. Due to erroneous purgation, toxin Qi enters the interior causing black collapse. First use Liu Qi Jian or Wen Wei Yin (Warm Stomach Drink) to nourish Stomach Qi. If exterior symptoms remain unresolved, subsequently use Chai Ge Gui Zhi Tang (Bupleurum, Pueraria, and Cinnamon Twig Decoction) to disperse externally; add Ma Huang for severe cases.
5. Due to unclean living quarters or contact with foul odors causing black collapse. Internally take Zi Cao Yin Zi (Arnebia Decoction), externally spray Hu Su Jiu, or use Yin Chen Moxibustion/Fumigation method, and apply Pi Xie Dan (Evil-Expelling Pill).
Third, during the rising phase, if blisters contain fluid but the color is dark/black, it is most alarming. Urgently use Liu Qi Jian added with Chuan Xiong (Ligusticum Rhizome) to invigorate Blood and Qi. When Blood and Qi are vigorous, toxins disperse and color becomes lively. Alternatively, use Shi Quan Da Bu Tang combined with Wu Jia San (Priceless Powder).
Fourth, regarding inverse crusting, one must observe the stool. If constipated with internal heat, promote drainage with Si Shun Qing Liang Yin or San Huang Wan (Three-Yellow Pill). If loose stools without internal heat, tonify with Liu Qi Jian or Shi Quan Da Bu Tang added with Fang Feng (Saposhnikovia Root) and Bai Zhi (Angelica Dahurica Root). For severe diarrhea, use Chen's Twelve-Ingredient Yi Gong San. For non-diarrheal but severe deficiency-cold, use Jiu Wei Yi Gong Jian and externally apply Bai Cao San (Decayed Grass Powder).
Fifth, there are three verification methods for treating collapse/trapping syndromes:
1. After medication, if collapsed areas swell again and gradually form pus, this is the first verification.
2. If original sores have dried but new layers emerge in empty spaces, rise, form pus, and gradually crust, this is the second verification.
3. If there is no swelling or emergence, but spontaneous diarrhea occurs passing pus and blood, while appetite and spirit remain normal, this is the third verification. Presence of verification signs indicates auspiciousness; absence indicates ominous prognosis.