上取妇人中 。近隐处。剪烧灰。以水和服方寸匕。日三服。小便即利。阴头微肿则愈。妇人病取男子 当烧灰。
（当即裆也。）
内台方议曰。大病新瘥。血气未复。余热未尽。强合阴阳。故曰易也。易者。如换易也。故与 中隐处烧灰服之。
以复其气也。男病用女。女病用男者。此以阴阳复易之义也。
琥按上议。即本成注之义。其云。回复其所易之气。此实发成注之未发。与仲景制方之旨。为甚相合。
琥又按烧 散。成注不言气味。仲景但云。小便即利。阴头微肿。则愈。此是言男子病。故曰阴头微肿。若妇人病。
止利小便而已。条辩云。 当近隐处。阴阳二气之所聚也。尚论篇云。服之小便得利。阴头微肿者。阴毒仍从阴窍出也。
此阴毒。当是阴中所受之毒。非阴寒之毒也。
琥又按所受之毒。有不尽从阴窍而得者。戴院使云。男子之病。秽气出于口。女子之病。秽气出于阴。然方其强合
之时。即女子口中。未必无秽气出者。及其施泄之后。即男子阴中亦未必无秽气下者。此皆不可拘也。全在医者。以意
会之。
大病瘥后。劳复者。枳实栀子汤主之。若有宿食者。加大黄。如博棋子大五六枚。（成注云。病有劳复。有食复。伤
寒新瘥。血气未平。余热未尽。早作劳动病者。名曰劳复。病热少愈。而强食之。热有所藏。因其谷气留搏。两阳相合
而病者。名曰食复。劳复则热气浮越。与枳实栀子豉汤以解之。食复则胃有宿积。加大黄以下之。愚按两阳相合而病。
以病热本属阳。而食入于阴。经又云长气于阳。故云两阳相合也。）
Take pubic hair from the female genital area near the concealed region, cut it off, and burn it to ash. Mix with water and administer one *cun* cube (approx. 2-3 grams) per dose, three times daily. When urination becomes smooth and the glans penis swells slightly, the patient will recover. If the patient is female, take the corresponding pubic hair from a male, burn it to ash, and administer it.
(This refers to the hair in the groin/crotch area.)
The *Neitai Fangyi* comments: After a severe illness has just healed, qi and blood have not yet recovered, and residual heat remains. Forcing sexual intercourse at this time leads to relapse, hence it is called "Yi" (Exchange/Change). "Yi" implies replacement or substitution. Therefore, administering the ash from the concealed genital area helps restore the disturbed qi mechanism. Using female hair for male patients and male hair for female patients follows the principle of yin-yang exchange.
Hu notes: The above commentary aligns with Cheng Wuji's original interpretation. His statement "restoring the qi that was exchanged/displaced" actually elucidates points Cheng did not explicitly state, closely matching Zhang Zhongjing's intent in formulating prescriptions.
Hu further notes: Cheng Wuji's commentary on the *Shaofa San* (Burnt Hair Powder) does not mention its flavor and nature. Zhang Zhongjing only states, "When urination becomes smooth and the glans penis swells slightly, the patient recovers." This description applies to male patients, hence the mention of the glans penis. For female patients, relief is indicated merely by smooth urination. *Tiaobian* states: "Hair should be taken from areas near the genitals, as these are sites where yin and yang qi gather." *Shanglun Pian* states: "After taking the medicine, if urination becomes smooth and the glans penis swells slightly, it indicates that 'yin toxin' is exiting through the yin orifice." This "yin toxin" refers to pathogenic factors acquired in the genital region, not necessarily cold-toxin.
Hu further notes: Pathogenic factors acquired may not always exit solely through the yin orifices. Dai Yuanli stated: "In male diseases, turbid qi exits from the mouth; in female diseases, turbid qi exits from the yin." However, during forced intercourse, turbid qi may also exit from the female's mouth; after ejaculation, turbid qi may descend from the male's yin. These situations should not be rigidly interpreted but require the physician's discernment.
For relapse due to overexertion after a severe illness has healed, *Zhishi Zhizi Tang* (Immature Bitter Orange and Gardenia Decoction) is the primary formula. If there is retained food stagnation, add *Dahuang* (Rhei Radix et Rhizoma), five to six pieces the size of a Go stone. (Cheng's commentary states: Relapse can be due to exertion (*Laofu*) or diet (*Shifu*). After new recovery from Cold Damage, qi and blood are unstable, and residual heat lingers. Engaging in labor too early causes *Laofu*. Eating strongly when fever symptoms subside traps heat; combined with grain qi retention and the interaction of two yangs, this causes *Shifu*. *Laofu* involves floating heat, treated with *Zhishi Zhizi Chidao Tang* (Immature Bitter Orange, Gardenia, and Fermented Soybean Decoction) to resolve it. *Shifu* involves gastric stagnation, treated with *Dahuang* to purge it. I note: 'Two yangs combining' refers to the fact that disease heat is inherently yang, while food enters the yin meridians; as the classics state 'yang qi grows,' thus two yangs combine.)