【方歌】缠腰火丹蛇串名，干湿红黄似珠形，肝心脾肺风热湿，
缠腰已遍不能生。
【注】此证俗名蛇串疮，有干湿不同，红黄之异，皆如累累珠
形。干者色红赤，形如云片，上起风粟，作痒发热。此
属肝心二经风火，治宜龙胆泻肝汤；湿者色黄白，水疱
大小不等，作烂流水，较干者多疼，此属脾肺二经湿热
，治宜除湿胃苓汤。若腰肋生之，系肝火妄动，宜用柴
胡清肝汤治之。其间小疱，用线针穿破，外用柏叶散敷
之；若不速治，缠腰已遍，毒气入脐，令人膨胀，闷呕
者逆。
方剂：龙胆泻肝汤
组成：龙胆草 连翘（去心）
生地 泽泻（各一钱）
车前子 木通
黄芩 黄连
当归 栀子（生研）
甘草（生，各五分） 生军（便秘加之，二钱）
水二钟，煎八分，食前服。
【方歌】龙胆泻肝火丹生，形如云片粟多红，芩连栀胆车归尾，
生地军翘泻木通。
又方：除湿胃芩汤
组成：苍术（炒） 厚朴（姜炒）
陈皮 猪苓
泽泻 赤茯苓
白术（土炒） 滑石
防风 山栀子（生研）
木通（各一钱） 肉桂
甘草（生，各三分）
水二钟，灯心五十寸，煎八分，食前服。
【方歌】除湿胃苓火丹疮，脾肺湿热疱白黄，胃苓汤用通栀子，
滑石防风共作汤。
又方：柏叶散
组成：侧柏叶（炒黄为末） 蚯蚓粪（韭菜地内者佳）
黄柏 大黄（各五钱）
雄黄 赤小豆
轻粉（各三钱）
上为细末，新汲水调搽，香油调搽更效。
【方歌】柏叶散搽火丹方，大黄赤豆柏雄黄，柏叶轻粉蚯蚓粪，
研末香油调更良。
又方：柴胡清肝汤（见头部鬓疽）
[Prescription Verse] Chanyao Huodan (Shingles), also known as Snake-String Disease, presents in dry and wet forms with red or yellow colors, resembling a string of pearls. The etiology involves wind-heat and dampness affecting the Liver, Heart, Spleen, and Lung meridians; if the rash encircles the waist completely, it is difficult to cure.
[Annotation] This condition is commonly known as Snake-String Sore. It is divided into dry and wet types, with red or yellow discoloration, and the morphology resembles linked pearls. In the dry type, the color is crimson, the shape is like cloud patches, surface eruptions resemble millet grains (wind-crops), accompanied by itching and fever. This belongs to wind-fire syndromes of the Liver and Heart meridians; treatment should employ Longdan Xiegan Tang (Gentiana Liver-Draining Decoction). In the wet type, the color is yellowish-white, vesicles vary in size, rupture and weep fluid, and are more painful than the dry type. This belongs to damp-heat syndromes of the Spleen and Lung meridians; treatment should employ Chushi Weiling Tang (Dampness-Removing Weiling Decoction). If occurring on the waist and hypochondrium, it is due to reckless movement of Liver fire; treatment should employ Chaihu Qinggan Tang (Bupleurum Liver-Clearing Decoction). Small vesicles within the eruption should be punctured with a thread needle, and Baiye San (Cypress Leaf Powder) applied externally. If not treated promptly, and the rash encircles the waist completely, with toxic qi entering the umbilicus causing abdominal distension, chest oppression, and vomiting, the prognosis is adverse (Ni syndrome).
Formula: Longdan Xiegan Tang (Gentiana Liver-Draining Decoction)
Composition: Gentianae Radix et Rhizoma (Longdancao), Forsythiae Fructus (Lianqiao, heart removed), Rehmanniae Radix (Shengdi), Alismatis Rhizoma (Zexie) (each 1 qian); Plantaginis Semen (Cheqianzi), Akebiae Caulis (Mutong); Scutellariae Radix (Huangqin), Coptidis Rhizoma (Huanglian); Angelicae Sinensis Radix (Danggui), Gardeniae Fructus (Zhizi, raw and crushed); Glycyrrhizae Radix et Rhizoma (Gancao, raw, each 0.5 qian); Rheii Radix et Rhizoma (Shengjun/Dahuang, add 2 qian for constipation).
Preparation and Administration: Decoct with two zhong of water until reduced to eight fen; take before meals.
[Prescription Verse] Longdan Xiegan Tang treats Huodan, presenting as cloud-like patches with many red millet-grain eruptions; the formula contains Huangqin, Huanglian, Zhizi, Longdancao, Cheqianzi, Dangguiwei, Shengdi, Dahuang, Lianqiao, Zexie, and Mutong.
Another Formula: Chushi Weiqin Tang (also known as Chushi Weiling Tang)
Composition: Atractylodis Rhizoma (Cangzhu, stir-fried), Magnoliae Officinalis Cortex (Houpo, ginger-stir-fried), Citri Reticulatae Pericarpium (Chenpi), Polypori Umbellatus (Zhuling), Alismatis Rhizoma (Zexie), Poria cum Ligno Quercus Rubra (Chifuling); Atractylodis Macrocephalae Rhizoma (Baizhu, earth-stir-fried), Talcum (Huashi), Saposhnikoviae Radix (Fangfeng), Gardeniae Fructus (Zhizi, raw and crushed), Akebiae Caulis (Mutong) (each 1 qian); Cinnamomi Cortex (Rougui), Glycyrrhizae Radix et Rhizoma (Gancao, raw, each 0.3 fen).
Preparation and Administration: Decoct with two zhong of water and fifty cun of Jiaxin (Centella asiatica herb/flower spike); reduce to eight fen; take before meals.
[Prescription Verse] Chushi Weiling Tang treats Huodan sores, addressing damp-heat of the Spleen and Lung causing yellow-white vesicles; the formula uses Weiling Tang added with Mutong and Zhizi, combined with Huashi and Fangfeng to make the decoction.
Another Formula: Baiye San (Cypress Leaf Powder)
Composition: Platycladi Cacumen (Baiye, stir-fried until yellow and powdered), Lumbricus Excrement (Earthworm feces, preferably from leek fields), Phellodendri Cortex (Huangbai), Rheii Radix et Rhizoma (Dahuang) (each 5 qian); Realgar (Xionghuang), Phaseoli Radiati Semen (Chixiaodou), Calomelas (Qingfen) (each 3 qian).
Usage: Grind all ingredients into a fine powder. Mix with fresh well-water for external application; mixing with sesame oil for external application is even more effective.
[Prescription Verse] Baiye San is an external application formula for Huodan, containing Dahuang, Chixiaodou, Huangbai, Xionghuang, Baiye, Qingfen, and Earthworm feces; grinding into powder and mixing with sesame oil yields better results.
Another Formula: Chaihu Qinggan Tang (See section on Bianju of the Head and Temples)