大黄（一两） 荆芥（二两）
每服末二钱。
内热小便不通者，此方主之。
内热而小便不通者，郁其少火，而气不化也。《内经》曰∶膀胱者，州都之官，津液藏
焉，气化则能出矣。然化气之道，莫妙于升降。天地以升而降化万物，奈何而昧于人乎？故
用荆芥之轻清者以升其阳。用大黄之重浊者以降其阴。清阳既出上窍，则浊阴自归下窍，而
小便随泄矣。方名倒换者，小便不通，倍用荆芥。大便不通，倍用大黄。颠倒而用，故曰倒
换。
车前子 瞿麦 蓄 滑石 山栀子（炒黑） 甘草梢 木通 大黄 木香
湿热下注，少腹急，小便不通者，此方主之。
湿热下注，令人少腹急，则小便有可行之势矣。而卒不通者，热秘之也。陶隐君曰∶通
可以去滞，泻可以去秘，滑可以去着。故用木通、瞿麦、 蓄通其滞，用大黄、山栀泻其秘。
用车前、滑石滑其着。用甘草梢者，取其坚实，能泻热于下。加木香者，取其辛香，能化气
于中。
大皂角一物，炒焦为末，炼蜜为丸梧子大。每服七丸，白汤下。
少腹急，小便不通，气不化者，此方亦良！
皂角之气，能通关开窍。皂角之味，能去垢涤污，故能化下焦之气，通膀胱之滞。
用炒盐热熨脐腹，冷复易之。
咸可以软坚，热可以行滞，此炒盐之意也。然必熨其脐者，脐为吾身之枢，有生之系也
，故能进气以化滞。
大黄（一两） 荆芥（二两）
每次服用药末二钱。
体内有热且小便不通畅的，此方主治。
体内有热而小便不通畅，是因为郁结导致少火（生理之火）受阻，气机无法气化。《黄帝内经》说：膀胱是州都之官，津液藏于其中，经过气化作用才能排出。然而气化的道理，没有比升降更精妙的了。天地依靠升与降来化育万物，怎么能对人体的机理感到困惑呢？所以用荆芥这种轻清的药物来升发阳气。用大黄这种重浊的药物来沉降阴气。清阳之气既已出于上窍，那么浊阴之气自然归于下窍，小便也就随之排泄了。方剂名为“倒换”的原因在于：如果是小便不通，加倍使用荆芥；如果是大便不通，加倍使用大黄。颠倒用药，所以称为倒换。
车前子 瞿麦 蓄草 滑石 山栀子（炒黑） 甘草梢 木通 大黄 木香
湿热向下注注，小腹部拘急疼痛，小便不通畅的，此方主治。
湿热向下注注，使人小腹部拘急，这就有了小便通行的趋势。但突然不通畅，是因为热邪秘结。陶隐君说：通利可以去除滞涩，泻下可以解除秘结，滑利可以去除黏着。所以用木通、瞿麦、蓄草来通利滞涩，用大黄、山栀子来泻下秘结。用车前子、滑石来滑利黏着。使用甘草梢，是取它质地坚实的特性，能向下泻热。加入木香，是取它辛香的特性，能在中焦化气。
大皂角一味药，炒焦后研为粉末，用炼蜜制成梧桐子大小的丸药。每次服用七丸，用白开水送服。
小腹部拘急疼痛，小便不通畅，气机不化的，此方也很好！
皂角的气味，能通关开窍。皂角的滋味，能去垢涤污，所以能化解下焦的气机，通利膀胱的滞涩。
用炒热的盐热敷脐部和腹部，冷了再更换。
咸味可以软坚散结，热性可以行气散滞，这就是炒盐的用意所在。然而必须熨敷脐部，是因为脐是人体气机的枢纽，是生命的系结所在，所以能引入正气以化解滞涩。
Rhizoma et Radix Rhei (Dahuang, 大黄) (1 liang), Folium Schisandrae Chinensis (Jingjie, 荆芥) (2 liang).
Take 2 qian of the powdered medicine each time.
For cases where there is internal heat and difficulty in urination, this formula is indicated.
Internal heat causing urinary obstruction results from the stagnation of Shaohuo (physiological fire), leading to impaired Qi transformation. The *Neijing* states: "The Bladder is the official of the Zhou Du (regional capital); it stores body fluids, and only through Qi transformation can they be excreted." However, the principle of Qi transformation lies best in ascending and descending. Heaven and Earth transform all things through ascent and descent; how can one be ignorant of this in relation to humans? Therefore, Jingjie, being light and clear, is used to ascend Yang Qi. Dahuang, being heavy and turbid, is used to descend Yin Qi. Once the clear Yang Qi has emerged from the upper orifices, the turbid Yin Qi naturally returns to the lower orifices, and urination follows. The formula is named "Daohuan San" (Reversed Exchange Powder) because: for urinary obstruction, Jingjie is doubled; for fecal obstruction, Dahuang is doubled. By reversing their usage, it is called "Daohuan."
Fructum Plantaginis (Cheqianzi, 车前子), Herba Dianthi (Qumai, 瞿麦), Herba Polygoni Avicularis (Bianxu, 蓄), Talcum (Huashi, 滑石), Fructus Gardeniae Jasminoidis (Shanzhizi, 山栀子) (stir-fried until black), Cauda Glycyrrhizae Uralensis (Gancao Shao, 甘草梢), Caulis Akebiae Trifoliate (Mutong, 木通), Rhizoma et Radix Rhei (Dahuang, 大黄), Rhizoma Aucklandiae (Muxiang, 木香).
For cases where damp-heat pours downward, causing urgency in the lower abdomen and urinary obstruction, this formula is indicated.
When damp-heat pours downward, it causes urgency in the lower abdomen, creating a tendency for urination to proceed. If it suddenly fails to pass, it is due to heat-induced constipation. Tao Yin Jun stated: "Unblocking can remove stagnation, purging can resolve constipation, and lubricating can remove adhesion." Therefore, Mutong, Qumai, and Bianxu are used to unblock stagnation; Dahuang and Shanzhizi are used to purge constipation. Cheqianzi and Huashi are used to lubricate adhesions. Gancao Shao is used for its solid nature, which allows it to drain heat downward. Muxiang is added for its pungent and aromatic nature, which transforms Qi in the middle jiao.
One piece of large Fructus Gleditsiae Sinensis (Zaojiao, 皂角), stir-fried until scorched, ground into powder, and formed into pills with refined honey the size of wu zi (loquat seeds). Take 7 pills each time, washed down with plain boiled water.
For cases of urgency in the lower abdomen, urinary obstruction, and impaired Qi transformation, this formula is also excellent!
The aroma of Zaojiao can open the orifices and unblock passages. Its taste can remove dirt and cleanse filth; thus, it can transform Qi in the lower jiao and unblock stagnation in the bladder.
Stir-fry salt until hot and apply as a compress to the umbilicus and abdomen; replace when it cools.
Salty flavor can soften hardness, and heat can promote the movement of stagnation; this is the rationale for using stir-fried salt. However, the umbilicus must be compressed because it is the pivot of the body's Qi and the tie of life; thus, it can introduce healthy Qi to resolve stagnation.