伤寒阴阳易之为病，其人身体重，少气，少腹里急，或引阴中拘挛，热上冲胸，头重不欲举，眼中生花，
膝胫拘急者，烧 散主之。
烧 散 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
子裆烧灰用。
尝治伤寒病未平复，犯房室死者，命在须臾。用独参汤调烧 散。凡服参一、二斤余得愈者三四人。信哉！
用药不可执一也。
治伤寒病新瘥，阴阳未和，因合房室，则令人阴肿，入腹绞痛，妇人则里急，腰胯连腹内痛，名为阴阳易
也。其男子病新瘥未平复，而妇人与之交接得病，名曰阳易；妇人病新瘥未平复，而男子与之交接得病，名曰
阴易。若二男二女，并不自相易，所以呼为易者，以阴阳相感动，其毒着于人，如换易然。其病之状，身热冲
胸，头重不能举，眼中生花，四肢拘急，小腹绞痛，手足拳则死。亦有不即死者，病苦少腹里急，热上冲胸，
头重不欲举，百节解离，经脉缓弱，血气虚、骨髓竭，便恍恍翕翕，气力转小，着床不能动摇，起止仰人，或
牵引岁月方死。宜烧 散、 鼠粪汤、竹茹汤、青竹茹汤、干姜汤、当归白术汤选用之。（海藏云∶
热者烧 散、竹皮汤，寒者 鼠粪汤、当归白术汤。至于《校正方》妙香丸条下，治杂病阴阳易中有牛黄、
脑、麝之类，是治其热症也。）
竹皮汤 疗交接劳复，卵肿，腹中绞痛欲绝。
竹皮青刮一升，用水三升，煮取一升，绞去渣，分二服，立愈。
青竹茹汤 妇人病未平复，因有所动，致热气冲胸，手足拘急搐搦，如中风状，宜此汤。
栝蒌根（一两） 青竹茹（刮半升，淡竹是）
上以水二升，煮取一升二合，去渣，分二、三服。
妙香丸（方见积热条。）
〔《百一》〕治交接劳复，阴卵肿，或缩入腹，腹绞痛，或便绝。蚯蚓数条，绞取汁，服之良。
〔海〕若阴阳易，果得阴脉，当随症用之。若脉在厥阴，当归四逆汤送下烧 散。若脉在少阴，通
脉四逆汤送下烧 散。若脉在太阴，四顺理中丸送下烧 散。所用之药，各随其经，而效自速也。
鼠粪汤 疗伤寒病后男子阴易。
韭白根（一把） 鼠粪（十四粒，两头尖者是）
上二味，以水五升，煮取半升，去渣，再煎三沸，温服得效。未汗，再服。亦理诸般劳复。
当归白术汤 治妇人未平复，因有所动，小腹急痛，腰胯四肢不任，举动无力，发热者。
白术 当归 桂枝 附子（生） 甘草 芍药 黄 人参（各二钱半） 生姜（半两）
上 咀，水煎服，食顷再服，温覆取微汗瘥。
李良佐子病太阳症，尺寸脉俱浮数，按之无力。余见其内阴虚，与神术加干姜汤。愈后再病，余视之，见
神不舒，垂头不欲语，疑其有房过，问之，犯房过乎？必头重目眩。曰∶唯。与大建中三四服，外阳
内收，脉
反沉小，始见阴候。又与已寒加芍药、茴香等丸五六服，三日内约服丸六七百丸，脉复生。又用大建中接之，
大汗作而解。
〔《山》〕因女色病阴证伤寒者，用陈皮热锅内炒焦，以酒烹下，滤酒饮之。
伤寒病后出现的“阴阳易”这种病症，患者身体沉重，气短乏力，小腹部拘急疼痛，或者牵引阴部痉挛紧缩，热气上冲至胸部，头部沉重不想抬起，眼前发黑视物模糊，膝盖和小腿拘挛僵硬，应当用烧裈散来主治。
烧裈散的制作方法是：取妇女贴身内裤靠近生殖器部位的布料，剪下来，烧成灰。用水调和，服用一方寸匕的药量，每天服用三次。服药后小便通畅，阴头轻微肿胀，就是痊愈的征兆。如果是女性患病，则取男子的裆部布料烧灰使用。
我曾经治疗过因伤寒病尚未完全康复就进行房事而死亡的病人，病情危急，命在旦夕。我用独参汤调服烧裈散。凡是服用人参一两、二两以上而痊愈的，有三四个人。确实如此！用药不能固执守旧。
治疗伤寒病刚刚痊愈，体内阴阳之气尚未调和，因为行房事，导致男子阴囊肿胀，痛入腹中绞痛；女子则感觉小腹拘急，腰胯连带腹部内部疼痛，这叫做“阴阳易”。如果男子病刚愈尚未恢复，与女子交合而得病，名叫“阳易”；女子病刚愈尚未恢复，与男子交合而得病，名叫“阴易”。如果是两个男人或两个女人之间，并不会互相传染致病，之所以称为“易”，是因为阴阳相互感应，邪毒附着于人身上，就像换衣服一样更换了体质。这种病的症状是：身体发热，热气上冲胸部，头部沉重无法抬起，眼前发黑视物模糊，四肢拘挛僵硬，小腹部绞痛，手足蜷缩则死。也有不立即死亡的，痛苦于小腹部拘急疼痛，热气上冲胸部，头部沉重不想抬起，全身关节松散无力，经脉弛缓虚弱，气血亏虚、骨髓枯竭，精神恍惚不定，气力逐渐减弱，卧床不能动弹，起床行走需要依靠他人，或者拖延岁月才死亡。适宜选用烧裈散、鼠粪汤、竹茹汤、青竹茹汤、干姜汤、当归白术汤等方剂进行治疗。（张元素海藏云：热证用烧裈散、竹皮汤，寒证用鼠粪汤、当归白术汤。至于《校正方》妙香丸条目下，治疗杂病中的阴阳易含有牛黄、脑、麝香之类，这是治疗热症的方法。）
竹皮汤：治疗因房事导致的劳复，睾丸肿胀，腹中绞痛欲绝。
取刮下的青竹皮一升，用水三升，煮取一升，过滤去渣，分两次服用，立刻痊愈。
青竹茹汤：女子病未完全康复，因有所触动，导致热气上冲胸部，手足拘挛抽搐，像中风的样子，适宜用此汤。
栝蒌根（一两） 青竹茹（刮半升，以淡竹为宜）
以上药材用水二升，煮取一升二合，过滤去渣，分两到三次服用。
妙香丸（方剂见积热条）。
〔《百一选方》〕治疗因房事导致的劳复，阴囊肿胀，或者缩入腹中，腹中绞痛，或者大便不通。取蚯蚓数条，绞取汁液，服用效果良好。
〔张元素海藏〕如果是阴阳易，果然诊得阴脉，应当随证施用。如果脉象在厥阴经，用当归四逆汤送服烧裈散。如果脉象在少阴经，用通脉四逆汤送服烧裈散。如果脉象在太阴经，用四顺理中丸送服烧裈散。所用的药物，各随其所属经络，疗效自然迅速。
鼠粪汤：治疗伤寒病后男子患阴易。
韭菜白根（一把） 鼠粪（十四粒，两头尖的为好）
以上两味药，用水五升，煮取半升，过滤去渣，再煎煮三沸，温服见效。若未出汗，再服用一次。也能调理各种劳复。
当归白术汤：治疗女子病未完全康复，因有所触动，小腹部急痛，腰胯四肢不胜任，举动无力，伴有发热的情况。
白术 当归 桂枝 附子（生用） 甘草 芍药 黄芪 人参（各二钱半） 生姜（半两）
以上药材切碎，用水煎服，过一会儿再服，温覆取微汗即愈。
李良佐的儿子患有太阳病，寸关尺三部脉都浮数，但按之无力。我见他内里阴虚，给予神术加干姜汤。病愈后又复发，我观察他，见他神情不舒，低头不想说话，怀疑他有房事过度，问他是否犯了房事？必定头痛目眩。他说：“是的。”于是给予大建中汤，服用三四次后，外阳内敛，脉象反而沉小，这才显现出阴证的候象。又给予已寒加芍药、茴香等丸药五六服，三天内大约服用了六七百丸，脉象重新出现。又用大建中汤接续治疗，大汗发出而病解。
The disease known as Yin-Yang Exchange (Yin Yang Yi) following a Shanghan (Cold Damage) illness is characterized by the patient having a heavy body, shortness of breath, urgency and pain in the lower abdomen, or spasms drawing into the genitalia, heat rushing up to the chest, heaviness of the head making it unwilling to be lifted, visual disturbances such as seeing spots before the eyes, and stiffness and cramping of the knees and calves. This should be primarily treated with Shao Kun San (Burning Underwear Powder).
To prepare Shao Kun San: Take the part of a woman's undergarment closest to the genitals, cut it off, and burn it to ash. Mix with water and administer one Fang Cun Bi (a square-inch measure) per dose, three times a day. When urination becomes smooth and the glans penis swells slightly, the patient will recover. If the patient is female, take the crotch part of a man's undergarment, burn it to ash, and use it.
I once treated a person who died because they engaged in sexual intercourse before their Shanghan illness had fully resolved; their life was hanging by a thread. I used Du Shen Tang (Single Ginseng Decoction) to mix with Shao Kun San. There were three or four cases where patients recovered after consuming more than one or two jin (approx. 500-1000g) of ginseng. Truly! One must not be rigid in the use of medicines.
Treating a case where a Shanghan illness has just healed, but Yin and Yang are not yet harmonized, and sexual intercourse leads to swelling of the yin (genitals) and severe abdominal colic in men, or urgency in the lower abdomen and pain connecting the waist, hips, and inner abdomen in women, this is named Yin-Yang Exchange. If a man whose illness has just healed engages in intercourse with a woman and contracts the disease, it is called Yang Exchange; if a woman whose illness has just healed engages in intercourse with a man and contracts the disease, it is called Yin Exchange. If it occurs between two men or two women, they do not exchange diseases with each other. It is called "Exchange" because Yin and Yang mutually influence each other, and the pathogenic toxin attaches to the person, changing their condition like exchanging clothes. The symptoms of this disease include: fever, heat rushing to the chest, heaviness of the head preventing it from being lifted, visual disturbances, stiffness and cramping of the four limbs, severe pain in the lower abdomen, and curling of hands and feet leading to death. Some may not die immediately; they suffer from urgency and pain in the lower abdomen, heat rushing to the chest, heaviness of the head, sensation of joints separating, slack and weak meridians, deficiency of blood and Qi, exhaustion of bone marrow, mental confusion, decreasing strength, inability to move from bed, requiring others to help them rise and walk, or dragging on for months or years until death. Suitable formulas to select from include Shao Kun San, Shu Fen Tang (Mouse Feces Decoction), Zhu Ru Tang (Bamboo Shavings Decoction), Qing Zhu Ru Tang (Green Bamboo Shavings Decoction), Gan Jiang Tang (Dried Ginger Decoction), and Dang Gui Bai Zhu Tang (Angelica and Atractylodes Macrocephala Decoction). (Zhang Yuansu [Hai Zang] stated: For heat patterns, use Shao Kun San or Zhu Pi Tang; for cold patterns, use Shu Fen Tang or Dang Gui Bai Zhu Tang. Regarding the Miao Xiang Wan (Wonderful Incense Pill) entry in the *Jiaozheng Fang* treating miscellaneous Yin-Yang Exchange diseases containing Rhinoceros Horn [now banned/replaced], Brain, and Musk, these treat heat patterns.)
Zhu Pi Tang treats labor relapse due to intercourse, testicular swelling, and unbearable abdominal colic.
Take one sheng (approx. 600ml) of scraped green bamboo skin, add three sheng of water, boil down to one sheng, strain out the dregs, and divide into two doses for immediate recovery.
Qing Zhu Ru Tang is suitable for women whose illness has not fully resolved and who have been disturbed, causing heat to rush to the chest, resulting in stiffness, cramping, and convulsions of the hands and feet resembling wind-stroke.
Gua Lou Gen (Trichosanthes Root) (1 liang / approx. 37.5g)
Qing Zhu Ru (Scraped Green Bamboo Shavings, half sheng; light bamboo is preferred)
Add two sheng of water to the above ingredients, boil down to one sheng and two he (approx. 24ml), strain out the dregs, and divide into two or three doses.
Miao Xiang Wan (Formula see Accumulated Heat section).
[From *Bai Yi Xuan Fang*] Treats labor relapse due to intercourse, swelling of the scrotum, or retraction into the abdomen, abdominal colic, or constipation. Take several earthworms, squeeze out the juice, and take it; it is effective.
[Zhang Yuansu/Hai Zang] If Yin-Yang Exchange is confirmed and a Yin pulse is found, treat according to the syndrome. If the pulse is in the Jueyin channel, administer Shao Kun San with Dang Gui Si Ni Tang (Angelica Cinnamon Twig Decoction). If the pulse is in the Shaoyin channel, administer Shao Kun San with Tong Mai Si Ni Tang (Pulse-Recovering Four Reversal Decoction). If the pulse is in the Taiyin channel, administer Shao Kun San with Si Shun Li Zhong Wan (Four Smooth Spleen-Harmonizing Pill). The medicines used should correspond to their respective channels, and efficacy will be rapid.
Shu Fen Tang treats Yin Exchange in men after Shanghan illness.
Jiu Bai Gen (White Root of Chinese Chive) (one handful)
Shu Fen (Mouse Feces, 14 grains, those pointed at both ends are best)
Add five sheng of water to the above two ingredients, boil down to half a sheng, strain out the dregs, boil again for three boils, and take warm for effect. If sweating does not occur, take another dose. It also regulates various types of labor relapse.
Dang Gui Bai Zhu Tang treats women whose illness has not fully resolved, who have been disturbed, resulting in urgent pain in the lower abdomen, inability to bear movement in the waist, hips, and four limbs, weakness in action, and fever.
Bai Zhu (Atractylodes Macrocephala Rhizome)
Dang Gui (Angelica Sinensis Radix)
Gui Zhi (Cinnamon Twig)
Fu Zi (Aconite Lateral Root, raw)
Gan Cao (Licorice Root)
Shao Yao (Peony Root)
Huang Qi (Astragalus Root)
Ren Shen (Ginseng Root) (each 2.5 qian / approx. 9.4g)
Sheng Jiang (Fresh Ginger) (half liang / approx. 18.75g)
Chop the above ingredients, decoct in water, take, and repeat after a meal period. Cover warmly to induce slight sweating for recovery.
Li Liangzuo's son suffered from a Taiyang pattern; the pulse at Cun, Guan, and Chi positions was floating and rapid, but forceless upon pressure. I observed his internal Yin deficiency and prescribed Shen Shu Jia Gan Jiang Tang (Atractylodes Formula with Dried Ginger). After recovery, the illness recurred. Upon examination, he appeared listless, keeping his head down and unwilling to speak. Suspecting excessive sexual activity, I asked if he had engaged in intercourse, predicting headache and dizziness. He agreed. I administered Da Jian Zhong Tang (Major Construct the Middle Decoction); after three or four doses, external Yang retreated inward, and the pulse became sinking and small, revealing Yin signs. I then administered pills containing Han Jiang (likely referring to a specific preparation or herb contextually linked to cold/deficiency), Shao Yao, and Hui Xiang (Fennel) for five or six doses. Within three days, approximately six or seven hundred pills were taken, and the pulse returned. Finally, I used Da Jian Zhong Tang again, leading to profuse sweating and resolution of the disease.
[From *Shan*] For Yin-pattern Shanghan caused by sexual indulgence, stir-fry Chen Pi (Tangerine Peel) in a hot pan until charred, cook with wine, filter, and drink the wine.