伤寒发斑，热甚而伤血，血热不散，里实表虚，热气乘虚出于皮肤而为斑也。轻则疹
子，甚则如锦纹。或病本属阳，误投热药，或当汗不汗，当下不下，或汗下未解，皆能至
此。有下之太早，热气乘虚入胃，故发斑；下之太迟，热留胃中，亦发斑；阳证热药过多，
胃热焦烂，亦皆发斑也。有表虚里实，热毒不散，所以不可轻发汗，不可轻下。阳毒发斑者，
若热毒深入，斑发紫黑，是毒陷于内，不可治也。斑赤者逆；黑者十死一生。
【消散】阳毒已深，内外结热，舌卷焦黑，鼻如烟煤，狂言见鬼，面赤，斑如锦纹，
五日可治，六七日不可治，阳毒升麻汤、人参白虎汤。始用热炽，发为赤斑或咽痛，
玄参升麻汤。表证多者，防风通圣散去硝黄。
【解利】温毒发斑而呕者，葛根橘皮汤。呕吐清汁，眼赤口疮下痢，黄连橘皮汤。
【解热】伤寒五六日斑出，猪胆鸡子汤。兼咽痛，紫雪，细细咽之。发赤斑，大青四
物汤。发斑通用升麻汤、犀角地黄汤。热多、玄参升麻汤、黄连四物汤、青木香一物汤。
【凉血】温毒发斑，冬月大暖，人受不正之气，至春发为斑烂瘾疹如锦纹，谓之温毒。
阳脉浮数，阴脉实大，黑膏化毒丹。
【下】温毒身无大热，渴烦大便实，腹痛，有赤斑瘾疹者，调胃承气汤。斑见无大热，
脉虚秘闷，当归丸。
【清补】汗下后胃虚极而发斑者，此火游于外所致，白虎加人参、白术。
In the context of *Shanghan* (Cold Damage) disease, the appearance of macules (skin eruptions) occurs when heat pathogen is extremely severe and damages the blood level. The resulting blood-heat stagnates and fails to dissipate; the interior is characterized by excess heat while the exterior exhibits deficiency. The heat qi takes advantage of this deficiency to emerge through the skin, forming macules. Mild cases present as papules (rashes), while severe cases resemble the patterns of brocade.
This condition may arise if the original disease was Yang-type but hot-natured medicines were mistakenly administered; or if sweating for exterior release or purging for interior excess was indicated but not performed; or if the pathogen remained unresolved after sweating or purging therapies.
If purging is performed too early, heat qi enters the Stomach due to deficiency, causing macules; if purging is delayed, heat remains stagnant in the Stomach, also causing macules. Furthermore, excessive use of hot medicines in Yang-patterns can scorch and rot the Stomach heat, similarly leading to macules.
When there is exterior deficiency with interior excess, and heat-toxin is constrained and undissipated, one must not lightly employ sweating methods, nor lightly employ purging methods.
In Yang-toxin macules, if the heat-toxin penetrates deeply and the macules turn purple-black, it indicates that the toxin has collapsed inward, which is incurable. Red macules indicate a adverse prognosis; black macules imply a mortality rate where only one in ten survives.
[Resolution] For deep-seated Yang-toxin with internal and external heat binding, presenting with tongue retraction and scorched-black coating, nose resembling soot smoke, delirium with hallucinations of seeing ghosts, red face, and brocade-like macules: treatment within five days is feasible, but after six to seven days it becomes untreatable. Formulas include Yang Du Sheng Ma Tang (Yang-Toxin Cinnamon Twig and Corydalis Decoction) and Renshen Baihu Tang (Ginseng White Tiger Decoction).
If initially the heat is blazing, causing red macules or sore throat, Xuan Shen Sheng Ma Tang (Scrophularia and Corydalis Decoction) is used. If exterior symptoms are predominant, Fang Feng Tong Sheng San (Saposhnikovia Universal Relief Powder) is used, excluding Mang Xiao (Mirabilite) and Da Huang (Rhubarb).
[Relief] For Wen Du (Warm Toxicity) macules accompanied by vomiting, Ge Gen Ju Pi Tang (Pueraria and Tangerine Peel Decoction) is prescribed. If vomiting clear fluids occurs with red eyes, mouth ulcers, and dysentery, Huang Lian Ju Pi Tang (Coptis and Tangerine Peel Decoction) is used.
[Heat-Resolving] For macules appearing on the fifth or sixth day of Shanghan, Zhu Dan Ji Zi Tang (Pig Gallbladder and Egg Yolk Decoction) is applied. If accompanied by sore throat, Zi Xue (Purple Snow) is taken slowly via swallowing. For red macules, Da Qing Si Wu Tang (Isatis Four Substances Decoction) is used. General formulas for macules include Sheng Ma Tang (Corydalis Decoction) and Xi Jiao Di Huang Tang (Rhinoceros Horn Rehmannia Decoction). For cases with abundant heat, Xuan Shen Sheng Ma Tang, Huang Lian Si Wu Tang (Coptis Four Substances Decoction), or Qing Mu Xiang Yi Wu Tang (Aucklandia Single Herb Decoction) may be employed.
[Blood-Cooling] Wen Du macules occurring during abnormally warm winters, where the body contracts irregular Qi, manifesting in spring as macerated macules and urticaria resembling brocade, is termed Wen Du. With floating-rapid pulse at the Yang position and solid-large pulse at the Yin position, Hei Gao Hua Du Dan (Black Ointment Toxin-Resolving Pill) is indicated.
[Purging Method] For Wen Du patients without significant fever but with thirst, irritability, solid stool, abdominal pain, and red macules/urticaria, Tiao Wei Cheng Qi Tang (Regulate the Stomach and Restore the Qi Decoction) is used. If macules appear without high fever, accompanied by deficient pulse and constipation with stifling sensation, Dang Gui Wan (Angelica Sinensis Pill) is prescribed.
[Clearing and Tonifying] When macules appear after sweating or purging due to extreme Stomach Qi deficiency, caused by Fire wandering outward, Bai Hu Jia Ren Shen Tang (White Tiger Plus Ginseng Decoction) and Bai Zhu (Atractylodes Macrocephala Rhizome) are utilized.