《病源论》云∶邪气客于皮肤，复逢风寒相折，则起风瘙隐疹。
若赤疹者，由凉湿折于肌中之热，热结成赤疹也。得天热则剧，取冷则减也。
白疹者，由风气折于肌中热，热与风相搏为白疹也。得天阴雨冷则剧出风中亦剧，得晴
温则
《素问》云∶赤疹忽起如蚊（亡云反，啮人虫也）蚋（竹合反，斑身小虻也），烦痒重
沓垄起，
《短剧方》白疹方∶
宜煮蒴 汤，与（羊洳反，参也）少酒，以浴佳。
又方∶以酒煮石南草，拭之。
又方∶水煮矾石汁，拭之。
又云∶赤疹方∶
宜生蛇衔草涂之，最验。大法如治丹诸方。
《千金方》治隐疹百治不瘥方∶
景天一斤，一名慎火，捣绞取汁，涂上。热灸手摸之，再三度即瘥。
又方∶矾石二两，末，酒三升渍令洋，拭上立瘥。
又方∶白芷叶煮汤洗之。
又方∶芒硝八两，水一斗，煮取四升，湿绵拭。
又∶淋锻石汁洗。
又方∶大豆三升，酒六升，煮四五沸，服一杯，日三。
《如意方》治隐疹术∶
漏芦作汤，以洗浴。
《效验方》治风搔茱萸汤方∶
茱萸（一升） 酒清（五升）
凡二物，合，煮得一升五合，绞去滓，适寒温洗，日三。
《录验方》黄连汤治风搔隐疹方∶
芒硝（五两） 黄连（五两）
凡二物，以水八升，煮取四升，去滓，洗风痒处，日二。良。
《本草稽疑》风搔隐疹方∶
煮蚕砂汁，渍之。
又方∶柠茎单煮洗之。
又方∶茺蔚叶可作浴汤。
《孟诜食经》风搔隐疹方∶
煮赤小豆取汁，停冷洗之。
The *Zhubing Yuanhou Lun* (Treatise on the Pathogenesis and Symptoms of All Diseases) states: When pathogenic factors lodge in the skin, and are further compromised by wind-cold, wind-sao yin-zhen (urticaria/pruritus) arises.
If it is chi-zhen (red urticaria), it occurs because cool-dampness restricts the heat within the muscles, causing the heat to congeal into red urticaria. The condition worsens with hot weather and improves upon exposure to cold objects.
If it is bai-zhen (white urticaria), it occurs because wind restricts the heat within the muscles, and the heat combats with wind to form white urticaria. The condition worsens during cloudy, rainy, or cold weather, or when exposed to wind, and improves during sunny and warm weather.
The *Suwen* (Basic Questions) states: Chi-zhen (red urticaria) suddenly appears like bites from mosquitoes (wang-yun fan, insects that bite humans) and horseflies (zhu-he fan, small flies with spots on their bodies); there is severe itching and irritation, with layers of raised welts.
The *Duanju Fang* (Short Drama Prescriptions) for treating bai-zhen (white urticaria):
It is suitable to decoct Shuobo Tang (Decoction of Ficus tikoua), add a small amount of wine, and bathe; this is excellent.
Another prescription: Decoct Shinancao (Rhododendri Mollis Caulis et Folium) in wine and wipe the affected area.
Another prescription: Decoct Fanshi (Alumen) in water, and wipe the affected area.
It also states: For treating chi-zhen (red urticaria):
It is suitable to apply fresh Sheyancao (Siphonostegiae Herba) topically; this is most effective. The general principle follows the prescriptions for treating Dan-du (erysipelas).
The *Qianjin Fang* (Essential Prescriptions Worth a Thousand Gold) for treating yin-zhen (urticaria) that has not healed after numerous treatments:
Jingtian (Portulaca oleracea), also known as Shenhuo, one jin. Crush and squeeze to obtain the juice, then apply topically. Apply hot moxibustion or massage with hands; repeating this several times will lead to recovery.
Another prescription: Fanshi (Alumen), two liang, powdered. Soak in three sheng of wine until turbid, then wipe the affected area for immediate recovery.
Another prescription: Wash with decoction made from Baizhiye (Angelica dahurica leaves).
Another prescription: Mangxiao (Natrii Sulfas), eight liang, and ten dou of water. Decoct to obtain four sheng. Wipe with moist cotton.
Another prescription: Wash with liquid from Duan-shi (Calcined Alumen).
Another prescription: Da-dou (Glycine max), three sheng, and six sheng of wine. Boil for four or five boils. Take one bei (cup), three times daily.
The *Ruyi Fang* (Prescription of Satisfaction) for treating yin-zhen (urticaria):
Make a decoction of Loulu (Euphorbiae Pekinensis Radix) and use it for bathing.
The *Xiaoyan Fang* (Effective Prescriptions) for treating wind-sao (wind-induced pruritus) Zhuyu Tang (Cornelian Cherry Decoction):
Zhuyu (Cornus officinalis), one sheng; Jiuqing (Clear wine), five sheng.
Combine these two ingredients, decoct to obtain one sheng and five he, strain to remove dregs, and wash at a comfortable temperature, three times daily.
The *Luyan Fang* (Recorded Effective Prescriptions) Huanglian Tang (Coptis Decoction) for treating wind-sao yin-zhen (wind-induced pruritus and urticaria):
Mangxiao (Natrii Sulfas), five liang; Huanglian (Coptidis Rhizoma), five liang.
Combine these two ingredients, add eight sheng of water, decoct to obtain four sheng, strain to remove dregs, and wash the pruritic areas, twice daily. This is good.
The *Bencao Qiyi* (Doubts on Materia Medica) for treating wind-sao yin-zhen (wind-induced pruritus and urticaria):
Decoct Can-sha (Bombyx Batryticatus residue/Castor bean residue? Note: Context implies silkworm excrement, Bombyx faeces) juice and soak the affected area.
Another prescription: Decoct Ning-jing (likely a typo or variant name, possibly referring to a specific plant stem) alone in water and wash.
Another prescription: Chongweiye (Leonuri Fructus/Leaf? Note: Usually refers to Leonurus japonicus herb/leaf) can be used as a bathing decoction.
The *Mengshen Shijing* (Meng Shen's Food Classic) for treating wind-sao yin-zhen (wind-induced pruritus and urticaria):
Decox Chi-xiaodou (Vigna angularis) to obtain the juice, let it cool, and wash the affected area.