经曰。诸寒为痛。又曰。甚热则痛。又曰。诸痛为实。三说不同。各有其理。当热作之时。毒
始营运。忽遇暴寒折之。毒邪壅于皮肤之间。不能宣发。此因寒而痛也。宜透肌运表。如烦躁渴
甚。狂言 语。便秘溺赤。更值春暄夏炎之令。痘见干红焦紫。就火热而痛甚。就阴凉而痛衰。
此因热而痛也。宜清凉化毒。若身不壮热。口不烦渴。饮食如常。二便清调。痘见尖绽红泽。至
七八日浆极充满。惟觉根窠胀痛。此诸痛为实。宜平和疏养。若初出而身痛者。为发未尽。升麻
汤。冬月加蜜炙麻黄二三分。既出稠密而身痛。为毒盛瘀血也。犀角消毒饮倍连翘加紫草。兼腰
背痛者。肝盛血凝也。泻青丸减大黄加甘草、防风。便秘腹胀。四肢厥冷。腰痛疮色紫黑者。难
治。百祥丸。若遍身如啮而色紫者。瘀毒壅滞。最危之兆。若二便秘结。喘急烦躁。栀子仁散。
自利不食者。不治。若身后痛属太阳经。用羌活、防风、甘草。身前痛属阳明经。用升麻、葛根、
紫草。身侧痛属少阳经。用连翘、柴胡、防风。四肢痛属脾经。用防风、芍药、甘草急止之。盖
恐叫号伤气。
忍痛伤血。而致变证也。若食鸡鱼酒物而致者。清胃散加生犀汁。大凡痘疮。切不可食毒物。恐
作痛致伤元气。轻者反重。重者难治。然有专取毒物以攻其毒。如猪尾膏、鸡冠血、攻毒汤等方
之义。不可以此碍彼也。
《黄帝内经》说：各种寒邪会导致疼痛。又说：极热也会导致疼痛。还说：各种疼痛多属于实证。这三种说法虽然不同，但各有其道理。
当痘疹发热发作时，毒邪开始运行，忽然遇到暴寒侵袭遏制它，导致毒邪壅滞于皮肤之间，不能宣散发越，这是因寒而致的疼痛。适宜采用透达肌表、运化表邪的方法治疗，如使用升麻汤（Shengma Tang, Corydalis Decoction）。如果伴有烦躁、极度口渴、胡言乱语、大便秘结、小便短赤，又正值春季温暖、夏季炎热之时，痘疹呈现干枯、红紫焦黑之象，疼痛在受热时加剧，在阴凉处减轻，这是因热而致的疼痛。适宜采用清凉解毒的方法治疗。
如果身体没有高热，口中不烦渴，饮食正常，大小便清利调和，痘疹尖部绽开、色泽红润光泽，到了七八天浆液极其充满，只感觉根部窠臼胀痛，这属于“诸痛为实”的情况。适宜采用平和疏养的方法治疗。
如果痘疹刚发出就出现身体疼痛，是因为痘毒尚未发尽，可用升麻汤；冬季加蜜炙麻黄二三分。如果痘疹已经出得稠密而出现身体疼痛，是因为毒盛且伴有瘀血，可用犀角消毒饮（Xijiao Xiaodu Yin, Rhinoceros Horn Detoxification Drink）倍用连翘并加入紫草。
如果兼有腰背疼痛，是肝气盛而血液凝滞所致，可用泻青丸（Xieqing Wan, Draining the Liver Pill）减去大黄，加入甘草、防风。
如果大便秘结、腹部胀满、四肢厥冷、腰痛且疮色紫黑，属于难治之症，可用百祥丸（Baixiang Wan, Hundred Auspicious Pills）。
如果遍身疼痛如同被虫咬，且颜色紫暗，是瘀毒壅滞的表现，是最危险的征兆。如果大小便同时秘结，气喘急促、烦躁不安，可用栀子仁散（Zhizi Ren San, Gardenia Seed Powder）。
如果自发性腹泻且不能进食，属于不治之症。
如果身体后部疼痛，属于太阳经病变，用羌活、防风、甘草。身体前部疼痛，属于阳明经病变，用升麻、葛根、紫草。身体侧面疼痛，属于少阳经病变，用连翘、柴胡、防风。四肢疼痛，属于脾经病变，用防风、芍药、甘草急止疼痛。这是因为担心大声呼号会耗伤正气，忍耐疼痛会损伤血液，从而导致变证。
如果是食用鸡、鱼、酒等食物导致的疼痛，可用清胃散（Qingwei San, Clear Stomach Powder）加入生犀角汁。
大凡痘疮患者，切不可食用有毒之物，恐怕引起疼痛从而损伤元气，轻病反而加重，重病则难以治愈。然而，也有专门利用毒物来攻伐毒邪的方义，如猪尾膏、鸡冠血、攻毒汤等方的含义，不可以此限制彼法。
The *Yellow Emperor's Inner Classic* states: "Various cold pathogens cause pain." It also states: "Extreme heat causes pain." Furthermore, it states: "Various pains belong to excess patterns." Although these three statements differ, each has its own rationale.
When the fever of smallpox erupts, the pathogenic toxin begins to circulate. If suddenly encountered by violent cold that obstructs it, the toxic pathogen becomes stagnant between the skin and muscles, unable to be diffused and released. This is pain caused by cold. The appropriate treatment is to vent the muscle layer and move the exterior, such as using Shengma Tang (Corydalis Decoction). If accompanied by restlessness, extreme thirst, delirious speech, constipation, and dark urine, and if this occurs during the warm spring or hot summer seasons, with the pustules appearing dry, red, purple, and scorched, where pain intensifies in heat and subsides in coolness, this is pain caused by heat. The appropriate treatment is to clear heat and resolve toxicity.
If there is no high fever, no irritability or thirst in the mouth, normal diet, and clear and regulated urination and defecation, and if the pustule tips have opened with a ruddy and lustrous color, reaching the seventh or eighth day with the pus extremely full, yet only feeling distending pain at the root of the pustules, this falls under the category of "various pains belong to excess." The appropriate treatment is peaceful regulation and nourishment.
If body pain occurs immediately upon the eruption of the rash, it indicates that the toxin has not fully emerged; use Shengma Tang (Corydalis Decoction), adding two to three fen of honey-fried Ephedrae Herba (Mahuang) in winter. If body pain occurs after the rash has erupted densely, it indicates abundant toxin and blood stasis; use Xijiao Xiaodu Yin (Rhino Horn Detoxification Drink), doubling the dosage of Forsythiae Fructus (Lianqiao) and adding Lithospermi Radix et Rhizoma (Zicao).
If accompanied by lower back and back pain, it indicates liver qi excess and blood coagulation; use Xieqing Wan (Draining the Liver Pill), removing Rheum Palmatum Radix et Rhizoma (Dahuang) and adding Glycyrrhizae Radix et Rhizoma (Gancao) and Saposhnikoviae Radix (Fangfeng).
If constipation, abdominal distension, cold limbs, lower back pain, and purple-black lesion color are present, it is difficult to treat; use Baixiang Wan (Hundred Auspicious Pills).
If the entire body feels pain as if bitten by insects, with a purple-dark color, it indicates stagnation of stasis-toxin, which is a sign of critical danger. If both urination and defecation are obstructed, accompanied by panting, urgency, and restlessness, use Zhizi Ren San (Gardenia Seed Powder).
If spontaneous diarrhea occurs and the patient cannot eat, it is incurable.
Pain in the posterior part of the body belongs to the Taiyang Meridian; use Notopterygii Rhizoma et Radix (Qianghuo), Saposhnikoviae Radix (Fangfeng), and Glycyrrhizae Radix et Rhizoma (Gancao). Pain in the anterior part of the body belongs to the Yangming Meridian; use Cimicifugae Rhizoma (Shengma), Puerariae Radix (Gegen), and Lithospermi Radix et Rhizoma (Zicao). Pain on the lateral side of the body belongs to the Shaoyang Meridian; use Forsythiae Fructus (Lianqiao), Bupleuri Radix (Chaihu), and Saposhnikoviae Radix (Fangfeng). Pain in the four limbs belongs to the Spleen Meridian; use Saposhnikoviae Radix (Fangfeng), Paeoniae Radix Alba (Shaoyao), and Glycyrrhizae Radix et Rhizoma (Gancao) to stop the pain urgently. This is because crying out loudly damages Qi, while enduring pain damages Blood, potentially leading to complicated changes.
If the pain is caused by consuming chicken, fish, or alcohol, use Qingwei San (Clear Stomach Powder) added with fresh Rhinoceros Cornu juice. Generally, patients with smallpox must absolutely avoid eating toxic substances, lest they induce pain and damage Yuan Qi, causing mild cases to become severe and severe cases to become untreatable. However, there are principles of specifically using toxic substances to attack toxins, such as those found in formulas like Zhuwei Gao (Pig Tail Paste), Jiguan Xue (Chicken Comb Blood), and Gongdu Tang (Toxin-Attacking Decoction); one should not let one principle hinder another.