痘疹大要。与痈疽治法无异。宜辨表里虚实寒热。盖表虚而用发表之剂。轻则斑烂。重则不
能起发而死。里实而用托里之剂。轻则患痘毒。重则喘急腹胀而死。里虚而用疏导之剂。轻则难
以灌脓结痂。重则不能结靥落靥而死。治法可不慎哉。若 赤发热疼痛作渴。能食便秘。此形气
病气俱实也。虽在严冬。必用四顺清凉饮。以救其阴。若黑陷不食。呕吐泄泻。寒战切牙。手足
逆冷。此脾土虚败。寒水所侮也。虽在盛暑。必用六君、姜、附。或陈氏异功散。以回其阳。此
内经舍时从证之法也。若起发迟不红活。不作脓。不结痂。或发热作渴。饮食少思。此脾胃虚弱
也。参 四圣散补之。若虽起而色白。虽灌脓而不满。虽结痂而不落。或痒塌作渴饮汤。腹痛不
食。呕吐泄泻。此脾胃虚寒也。陈氏木香散以温之。其在四五日之间死者。毒瓦斯盛。真气虚而不
能起发也。六七日之间死者。元气虚而不能灌脓也。旬日之外死者。邪气去。脾胃败而元气内脱
也。治者但能决其死。而不知其死必本于血气亏损。苟能逆推其因而预为调补。岂断无生理哉。
盖起发灌脓结痂三者。皆由脾胃荣养。不可妄投克伐之剂以致其夭枉也。至于大人患此。治法迥
异。昔丹溪尝治一老人。初患痘。昏愦不知。亟用大补四十余剂。出痘而愈。观此可见。
痘疹的治疗要点，与痈疽的治疗方法没有不同。应当辨别表里、虚实、寒热。如果体表虚弱而使用发汗解表的药剂，轻则导致斑疹溃烂，重则不能起发透疹而死。如果体内实邪壅盛而使用补益托毒的药剂，轻则引发痘毒内陷，重则出现气喘急促、腹部胀满而死。如果体内虚弱而使用疏导通利的药剂，轻则难以化脓结痂，重则不能结靥（痘疮愈合）或结靥后脱落过早而死。治疗方法怎能不谨慎呢？
如果出现面色红赤、发热、疼痛、口渴、能进食、大便秘结，这是形体之气和病邪之气都属实证的表现。即使在严冬，也必须使用四顺清凉饮来救阴液。如果出现痘色黑陷、不能进食、呕吐泄泻、寒战咬牙、手足逆冷，这是脾土虚败，被寒水反侮的表现。即使在盛夏，也必须使用六君子汤加干姜、附子，或者陈氏异功散，来回阳救逆。这是《内经》中“舍时从证”的治疗方法。
如果痘疹起发迟缓、颜色不红润鲜活、不化脓、不结痂，或者伴有发热口渴、饮食减少、思食无力，这是脾胃虚弱的表现，用参四圣散来补益。如果虽然起发但颜色苍白，虽然化脓但不饱满，虽然结痂但不脱落，或者瘙痒塌陷、口渴想喝热水、腹痛不食、呕吐泄泻，这是脾胃虚寒的表现，用陈氏木香散来温中。
在发病四五日之间死亡的，是毒瓦斯旺盛，真气虚弱而不能起发所致。在发病六七日间死亡的，是元气虚弱而不能化脓所致。在发病旬日（十天）之外死亡的，是邪气已去，但脾胃败坏而元气内部脱失所致。治疗者如果能判断出死亡的原因，却不知道死亡的根本原因在于气血亏损，假如能逆向推究病因并预先进行调补，难道完全没有生机吗？
起发、化脓、结痂这三者，都依赖脾胃的荣养，不可妄投攻伐克削的药剂，以致导致夭折枉死。至于成年人患此病，治疗方法截然不同。过去朱丹溪曾治疗一位老人，起初患痘疹，神志昏愦不知人，紧急使用大补药剂四十余剂，痘疹发出后痊愈。从这可以看出其中的道理。
The key principles for treating smallpox and measles are no different from those for treating carbuncles and sores. It is essential to differentiate the exterior and interior, deficiency and excess, cold and heat. If the exterior is deficient and diaphoretic (sweat-inducing) formulas are used, mild cases may result in ulceration of the rash, while severe cases may fail to erupt and lead to death. If the interior is excess and tonifying/detoxifying formulas are used, mild cases may result in internal retention of toxin, while severe cases may lead to panting, abdominal distension, and death. If the interior is deficient and draining/advancing formulas are used, mild cases may fail to suppurate and form scabs, while severe cases may fail to crust over or shed prematurely, leading to death. How can treatment methods not be cautious?
If there is redness, fever, pain, thirst, ability to eat, and constipation, this indicates that both the constitutional qi and pathogenic qi are in an excess state. Even in severe winter, Si Shun Qing Liang Yin (Four-Obedience Cooling Decoction) must be used to nourish yin. If there is blackening and sinking of lesions, inability to eat, vomiting, diarrhea, chattering teeth due to cold, and cold extremities, this indicates failure of Spleen Earth being invaded by Cold Water. Even in peak summer, Liu Jun Zi Tang (Six-Gentlemen Decoction) with Gan Jiang (Dried Ginger) and Fu Zi (Prepared Aconite), or Chen Shi Yi Gong San (Mr. Chen’s Extraordinary Power Powder), must be used to restore yang. This is the method of "abandoning the season to follow the syndrome" described in the Nei Jing (Inner Canon).
If eruption is delayed, color is not vibrant or fresh, suppuration does not occur, and scabs do not form, accompanied by fever, thirst, poor appetite, and lack of desire to eat, this indicates Spleen and Stomach deficiency. Shen Si Sheng San (Ginseng Four-Saints Powder) should be used to tonify. If eruption occurs but color is pale, suppuration is incomplete, scabs do not shed, or if there is itching, collapse, thirst for hot drinks, abdominal pain, anorexia, vomiting, and diarrhea, this indicates Spleen and Stomach deficiency-cold. Chen Shi Mu Xiang San (Mr. Chen’s Costus Powder) should be used to warm.
Those who die between the fourth and fifth days have excessive toxins and deficient true qi unable to erupt. Those who die between the sixth and seventh days have deficient yuan qi unable to suppurate. Those who die after ten days have expelled pathogens but failed Spleen and Stomach function, leading to internal collapse of yuan qi. Practitioners who can only predict death without understanding that it stems from blood and qi deficiency, and who fail to reverse-engineer the cause and provide preventive regulation and tonification, miss the opportunity for survival. Eruption, suppuration, and scabbing all rely on the nourishment of the Spleen and Stomach; one must not recklessly administer attacking or reducing formulas, which would lead to premature death.
For adults suffering from this disease, the treatment method is entirely different. In the past, Danxi treated an elderly patient who initially suffered from smallpox with confusion and unconsciousness. He urgently administered forty-plus doses of major tonifying formulas, resulting in the eruption of lesions and recovery. This illustrates the principle.