痘疳，乃痘后余毒未尽，正气已亏，邪走空窍，是以口、鼻、眼、耳、前阴、后阴皆可成疳。治当败毒调元。
验方
牛粪尖（烧灰存性） 雄黄（各等分）
每钱加冰片二分，乳细搓患处，立愈。
陈实功曰∶痘风疮，是痧痘后毒发未尽，留热肌肤，后被外风侵入，其患先从
细疮作痒，次渐沿开，成片脂水，生痂搔之无度，宜用麦饯散擦之。（《正宗。》）
麦饯散 小儿痘风作痒，叠叠成片，甚则顽麻不知痛痒。
小麦一升炒枯黄色，乘热入钵内，和硫黄四两，白砒一两，研细待冷取起，加
烟胶半斤，川椒三两，生明矾、枯矾各二两，共研细末。临用葱汤洗净，以麻油调
搓，油纸盖扎三日一换，三次即愈。并治白秃神效。
申斗垣曰∶痘出五七日后痒极，动手抓破，急用仙鹤翎在痘上扫一二次即止痒，
就不抓。此神验秘方也。（启玄）
申斗垣曰∶痘已愈，毒未全解，痂虽落尽，止有瘢痕尚在，或黑或凸或凹，或
成疮者，用真白蜜一两涂之，其瘢自消。（《启玄》）
胡公弼曰∶羊骨髓入轻粉研匀涂之，灭瘢。（《青囊》）
申斗垣曰∶痘后疮水不干，在肢体名曰痘疳。用出过蛾的蚕茧不拘多少，每个
入生明矾令满，炭火 研为末，掺之即干。（《启玄》）
又曰∶搔坏痘破烂者，用多年屋上腐草不拘多少，研极细，铺在席子上，令儿
卧其上，自不粘痛，或掺之亦妙。
痘疳，是痘疹痊愈后余留的毒邪尚未清除，人体正气已经亏损，病邪侵入空窍所致，因此口、鼻、眼、耳、前阴、后阴等部位都可能发生疳疮。治疗应当以解毒败毒、调理元气为主。
验方：
牛粪尖（烧成炭灰但保留药性）与雄黄（各取等量）。
每钱药粉中加入冰片二分，研磨细腻后搓擦患处，立即痊愈。
陈实功说：痘风疮，是痧痘之后毒邪未完全发散，余热滞留肌肤，随后被外感风邪侵入所致。病症起初从细小的疮疡开始瘙痒，逐渐蔓延成片，流出脂水，结痂后搔抓无度。适宜使用麦饯散擦拭。（《外科正宗》）
麦饯散：主治小儿痘风引起的瘙痒，层层叠叠成片，严重时皮肤麻木不知痛痒。
小麦一升炒至枯黄色，趁热放入钵内，加入硫黄四两、白砒一两，研磨细碎待冷却后取出，再加入烟胶半斤、川椒三两、生明矾和枯矾各二两，共同研磨成细末。使用时用葱汤洗净患处，用麻油调和后搓擦，用油纸覆盖包扎，三日更换一次，三次即可痊愈。此方对治疗白秃（头部癣疾）也有神奇疗效。
申斗垣说：痘疹发出五七日后瘙痒极其严重，患者动手抓破，急需用仙鹤翎在痘疹上扫一两次即可止痒，从而不再抓挠。这是神验秘方。（《启玄指掌》）
申斗垣说：痘疹已愈，但毒邪未完全解除，痂皮虽已落尽，仅留有瘢痕，有的颜色发黑，有的凸起，有的凹陷，有的形成疮疡，可用真白蜜一两涂抹，其瘢痕自然消退。（《启玄指掌》）
胡公弼说：将羊骨髓与轻粉研匀后涂抹，可消除瘢痕。（《青囊秘传》）
申斗垣说：痘疹后疮面流水不干，发生在肢体上的称为痘疳。使用吐过蛾子的蚕茧不限数量，每个蚕茧中填入生明矾使其充满，在炭火上煅烧研为粉末，撒在患处即可使疮面干燥。（《启玄指掌》）
又说：对于因搔抓导致痘疹破损溃烂者，可使用多年屋顶上的腐草不限数量，研磨极细，铺在席子上，让孩子睡在上面，自然不粘连疼痛，或者将腐草粉末直接撒在患处也很妙。
Douchan (Post-varicella ulceration) refers to the condition where residual toxins from smallpox/varioloid remain uneliminated after recovery, while the body's righteous qi is already deficient. The pathogenic factors invade the hollow orifices, thus causing chancre-like lesions in the mouth, nose, eyes, ears, anterior yin, and posterior yin. Treatment should focus on eliminating toxins and regulating the primal qi.
Empirical Formula:
Niu Fen Jian (Tip of cow dung), calcined to ash but retaining its medicinal nature; Xionghuang (Realgar). Use equal parts of each.
For every qian (approx. 3.7g) of powder, add Bingpian (Borneol) 2 fen (approx. 0.07g). Grind finely and rub onto the affected area for immediate cure.
Chen Shigong stated: Douchengchuang (Varicella wind-lesion) occurs when toxins from measles/smallpox are not fully dispersed after eruption, leaving residual heat in the skin. Subsequently, external wind pathogens invade. The condition begins with itching from fine pustules, gradually spreading into patches exuding serous fluid, forming scabs that are excessively scratched. It is suitable to use Maijiang San (Wheat Paste Powder) for wiping. (*Waike Zhengzong*)
Maijiang San: Indicated for children's varicella wind causing severe itching, presenting as overlapping patches, and in severe cases, causing numbness and loss of sensation.
Take one sheng (approx. 1L) of wheat, stir-fry until dark yellow. While hot, place it in a mortar, mix with Liuhuang (Sulfur) 4 liang (approx. 150g) and Baipi (White Arsenic) 1 liang (approx. 37.5g). Grind finely, allow to cool, then remove. Add Yanjiao (Tobacco gum/resin) half a jin (approx. 300g), Chuanjiao (Sichuan Pepper) 3 liang (approx. 112.5g), Sheng Mingfan (Raw Alum) and Kufan (Calcined Alum) 2 liang (approx. 75g) each. Grind all together into a fine powder. Before use, wash the area with green onion soup. Mix with Mayou (Sesame Oil) and rub onto the lesion. Cover with oil paper and bind; change once every three days. Three applications will result in a cure. This formula is also highly effective for treating Baitu (Tinea capitis/white baldness).
Shen Douyuan stated: Five to seven days after the eruption of varicella, itching becomes extreme, leading patients to scratch and break the lesions. Urgently use Xianheling (Feathers of the crane/heron) to sweep over the lesions one or two times to stop the itching immediately, preventing further scratching. This is a miraculous secret prescription. (*Qixuan Zhizhang*)
Shen Douyuan stated: After varicella has healed, if toxins are not fully resolved, and although scabs have fallen off, scars remain—some black, some convex, some concave, or forming ulcers—apply Zhen Baimi (Pure White Honey) 1 liang (approx. 37.5g). The scars will naturally disappear. (*Qixuan Zhizhang*)
Hu Gongbi stated: Apply Yang Guisui (Sheep bone marrow) mixed evenly with Qingfen (Calomel) to eliminate scars. (*Qingnang Mijuan*)
Shen Douyuan stated: When varicella sores weep continuously without drying up, occurring on the limbs, it is called Douchan. Use silkworm cocoons that have produced moths, quantity unrestricted. Fill each cocoon completely with Sheng Mingfan (Raw Alum). Calcine over charcoal fire, grind into powder, and sprinkle on the affected area to dry the sores. (*Qixuan Zhizhang*)
He also stated: For varicella lesions damaged by scratching and ulcerated, use rotting grass from old roofs, quantity unrestricted. Grind extremely finely, spread on a mat, and let the child lie upon it. This prevents sticking and pain. Alternatively, sprinkling the powder directly on the lesions is also excellent.