王肯堂曰∶夫人阳气外虚则多汗，汗
出当风，风气搏于肌肉，与热气并则生 ，状如麻豆，甚者渐大，搔之则成疮也。（《准绳》）
《心法》曰∶ 俗名鬼饭疙瘩，由汗出受风，或露卧乘凉，风邪多中表虚之人。
初起皮肤作痒，次发扁疙瘩，形如豆瓣，堆累成片，日间痒甚者，宜秦艽牛蒡汤，夜
间痒甚者，宜当归饮子，外用烧酒浸百部，以蓝布蘸酒搓之，谨避风凉。
陈实功曰∶癣乃风热湿虫四者而成。风宜散，热宜清，湿宜渗，虫宜杀，总由血
燥风毒克于脾肺二经耳。（《正宗》）
又曰∶风癣如云朵，皮肤娇嫩，抓之则起白屑，不知痛痒。
又曰∶湿癣如虫形，搔之则有汁出。
又曰∶顽癣抓之全不知痛。
又曰∶牛皮癣顽硬且坚，抓之如朽木。
又曰∶马皮癣微痒，白点相连。
又曰∶狗皮癣白斑相簇，时作微痒。
周文采曰∶干癣搔之则出白屑，索然雕枯。（《集验》）
又曰∶刀癣则轮廓全无，纵横不定。
申斗垣曰∶白壳疮即癣也。（《启玄》）
王肯堂曰∶面上风癣，初起 或渐成细疮，时作痛痒，发于春月，名曰花癣，
女人多生之。此皆肺经蕴积风热，阳气上升，发于面部或生眉目之间，久而不愈，恐成风疾。（《准绳》）
蒋示吉曰∶上半身为顽癣，治之易，多属风热。（《说约》）
又曰∶阴癣生在下半身，治之最难，多属寒湿，总之血分受病，以致皮肤不和也。
Weng Kentang stated: When the Yang Qi of the human body is deficient on the exterior, there is excessive sweating. If wind strikes while sweating, the Wind pathogen combats with Heat in the muscles and flesh, resulting in Xuan (Tinea/Lichen), which resembles hemp seeds or beans. In severe cases, it gradually enlarges; scratching it causes sores to form. (From *Yixue Zhunsheng*)
*Yixue Xinfa* states: Colloquially known as "Ghost Rice Wheals," this condition arises from exposure to wind during sweating, or sleeping outdoors and cooling off. The Wind pathogen often attacks individuals with Exterior Deficiency.
Initially, the skin itches, followed by the appearance of flat wheals resembling broad beans, accumulating in patches. For severe itching during the day, Qinjiao Niulang Tang (Gentian and Arctostaphylos Decoction) is appropriate; for severe itching at night, Danggui Yinzi (Angelica Decoction) is appropriate. Externally, use Shaobai (Bai Bu, *Stemonae Radix*) soaked in distilled liquor, applied by rubbing with blue cloth. One must strictly avoid wind and cold.
Chen Shigong stated: Xuan is formed by the combination of Wind, Heat, Dampness, and Parasites. Wind should be dispersed, Heat cleared, Dampness percolated, and Parasites killed. Ultimately, this stems from Blood Dryness and Wind-Toxin impairing the Spleen and Lung meridians. (From *Waike Zhengzong*)
He further stated: Fengxuan (Wind Tinea) resembles clouds; the skin is delicate, and scratching produces white scales without sensation of pain or itch.
He also stated: Shixuan (Damp Tinea) resembles insect shapes; scratching exudes fluid.
He also stated: Wanxuan (Stubborn Tinea) presents with no sensation of pain even when scratched.
He also stated: Nipixuan (Cowhide Tinea) is hard and firm; scratching feels like rotten wood.
He also stated: Mapixuan (Horse Skin Tinea) involves slight itching with connected white spots.
He also stated: Goupixuan (Dog Skin Tinea) features clustered white patches with occasional slight itching.
Zhou Wencai stated: Ganxuan (Dry Tinea) sheds white scales when scratched, appearing withered and dry. (From *Jiyan Fang*)
He also stated: Daoxuan (Knife Tinea) lacks clear contours and is irregular in distribution.
Shen Douyuan stated: Baikechuang (White Shell Disease) is synonymous with Xuan. (From *Qixuan Weizhi*)
Weng Kentang stated: Facial Fengxuan initially may gradually form small sores, presenting with intermittent pain and itch, occurring in spring months. It is named Huaxuan (Flower Tinea) and is more common in women. This results from accumulated Wind-Heat in the Lung Meridian, causing Yang Qi to ascend and manifest on the face or between the eyebrows and eyes. If unresolved over time, it may develop into Wind Diseases. (From *Yixue Zhunsheng*)
Jiang Shiji stated: Wanxuan on the upper half of the body is easier to treat and mostly belongs to Wind-Heat patterns. (From *Yizhong Shuyue*)
He also stated: Yin Xuan (Yin Tinea) occurs on the lower half of the body and is the most difficult to treat, mostly belonging to Cold-Damp patterns. In essence, the Blood level is affected, leading to disharmony of the skin.