当汤。今温疫起无表证。而惟胃实。故肠胃蓄血多。膀胱蓄血少。然抵当汤。行瘀逐蓄之最者。无分前后二便。
并可取用。然蓄血结甚者。在桃仁力所不及。宜抵当汤。盖非大毒猛厉之剂。不足以抵当。故名之。然抵当证。
所遇亦少。
抵当汤方
桃仁（二十个去皮尖○千金。二十三个。翼同本文。有熬字。） 水蛭（熬） 虫虻（各三十个去翅足熬）
大黄（三两酒洗○玉函。成本。酒浸。千金翼。作二两。破六片。）
上四味。以水五升。煮取三升。去滓。温服一升。不下更服。（四味下。玉函。成本。有为末二字。）
〔柯〕蛭。昆虫之巧于饮血者也。虻。飞虫之猛于吮血者也。兹取水陆之善取血者攻之。同气相求耳。
更佐桃仁之推陈致新。大黄之苦寒。以荡涤邪热。〔钱〕抵当者。言瘀血凝聚。固结胶粘。即用桃仁承气。及破
血活血诸药。皆未足以破其坚结。非此尖锐钻研之性。不能抵当。故曰抵当。
张氏医通曰。如无虻蛭。以干漆灰代之。
案抵当。方氏云。抵。至也。亦至当不易之正治也。喻氏汪氏辈皆同。锡驹云。抵拒大敌。四物当之。柯
氏云。抵当者。谓直抵其当攻之所也。
太阳病身黄。脉沉结。少腹硬。小便不利者。为无血也。小便自利。其人如狂者。血证谛也。抵当汤主之。
（千金。黄。作重。硬下。有满字。）
〔钱〕此又以小便之利与不利。以别血证之是与非是也。身黄。遍身俱黄也。沉为在里。而主下焦。结则脉
来动而中止。气血凝滞。不相接续之脉也。前云少腹当硬满。此则竟云少腹硬。脉证如此。若犹小便不利者。
终是胃中瘀热郁蒸之发黄。非血证发黄也。故为无血。若小便自利而如狂。则知热邪与气分无涉。故气化无乖。
其邪在阴血矣。此乃为蓄血发黄。〔柯〕湿热留于皮肤而发黄。卫气不行之故也。燥血结于膀胱而发黄。营气
不敷之故也。水结血结。俱是膀胱病。故皆少腹硬满。小便不利是水结。小便自利是血结。如字。助语辞。若
以如字实讲。与发狂分轻重。则谬矣。〔方〕谛。审也。言如此则为血证审实。无复可疑也。
案小便不利者。成氏云。可与茵陈蒿汤。补亡论云。与五苓散。程氏云。属茵陈五苓散。柯氏云。麻黄连
轺赤小豆汤症也。以上宜选而用之。
伤寒有热。少腹满。应小便不利。今反利者。为有血也。当下之。不可余药。宜抵当丸。（有热下。玉函。
脉经。外台。有而字。）
〔成〕伤寒有热。少腹满。是蓄血于下焦。若热蓄津液不通。则小便不利。其热不蓄津液。而蓄血不行。
小便自利者。乃为蓄血。当与桃仁承气汤。抵当汤下之。然此无身黄屎黑。又无喜忘发狂。是未至于甚。故不
可余 峻之药也。可与抵当丸。小可下之也。〔柯〕有热。即表证仍在。
抵当丸方
水蛭（二十个熬○周。吴。作二十个。猪脂熬黑。） 桃仁（二十五个去皮尖○玉函。外台。成本。三十个。
千金。二十二个。翼。有熬字） 虻虫（二十个去翅足熬○玉函。二十五个。） 大黄（三两）
上四味。捣分四丸。以水一升。煮一丸。取七合服之。 时当下血。若不下者更服。（千金。作上四味。
为末。蜜和合。分为四丸。）
〔柯〕小其制。而丸以缓之。方变汤为丸。然名虽丸也。犹煮汤焉。〔张〕煮而连滓服之。与大陷胸同意。
陶弘景云。 时者。周时也。从今旦至明旦。
太阳病小便利者。以饮水多。必心下悸。小便少者。必苦里急也。（病源。作太阳病。小便不利者。为多
饮水。心下必悸云云。非也。）
〔成〕饮水多。而小便自利者。则水不内蓄。但腹中水多。令心下悸。金匮要略曰。食少饮多。水停心下。
甚者则悸。饮水多而小便不利。则水蓄于内而不行。必苦里急也。〔钱〕水寒伤胃。停蓄不及即行。必令心下
悸动。心下者。胃之部分也。悸者。水满胃中。气至不得流通。而动惕也。〔程〕若小便少。而欲得水者。此渴。
热在下焦。属五苓散证。强而与之。纵不格拒。而水积不行。必里作急满也。〔汪〕常器之云。可茯苓甘草汤。
又猪苓汤。推常氏之意。小便利者。用茯苓甘草汤。小便少者。猪苓汤。
Should use Didang Tang (Cochineal and Leech Decoction). Currently, warm epidemic diseases arise without exterior syndromes, but only with Stomach excess (Gastrointestinal dryness-heat consolidation), so there is much blood stasis in the intestines and stomach, and little in the Bladder. However, Didang Tang is the most potent formula for moving blood stasis and eliminating accumulation (breaking down blood stasis and fluid retention). Regardless of whether the pathology is in the anterior or posterior orifices, it can be used. Nevertheless, when blood stasis is severely knotted, the power of Tao Ren (Peach Kernel) is insufficient, and Didang Tang is appropriate. Generally, unless it is a highly toxic and fierce preparation, it cannot withstand (attack) the solid knotting; hence the name "Didang" (Withstand/Attack). However, cases of Didang syndrome are encountered rarely.
Formula: Didang Tang (Cochineal and Leech Decoction)
Tao Ren (Peach Kernel, Semen Persicae, 20 seeds, remove skin and tips ○ *Qianjin Fang* uses 23 seeds, rest same as text, has "roasted" character.) Shui Zhi (Leech, Hirudo, roasted) Meng Chong (Dragonfly Larva, Odonata larva, each 30, remove wings and feet, roasted)
Da Huang (Rhubarb Radix et Rhizoma, 3 liang, washed with wine ○ *Yuhan Jing*, Chengben edition: soaked in wine; *Qianjin Yi Fang*: 2 liang, broken into six pieces.)
The above four herbs, boil in five sheng of water to obtain three sheng, remove dregs, take one sheng warm. If stool does not pass, take again. (After the four herbs, *Yuhan Jing* and Chengben have "make into powder" two characters.)
[Ke Qin] Shui Zhi (Leech) is an insect skilled at drinking blood. Meng Chong (Dragonfly Larva) is a flying insect fierce at sucking blood. Here we use land and water creatures good at taking blood to attack, which is seeking resonance by similar qi.
Additionally assisting with Tao Ren (Peach Kernel) to push out the old and generate the new, and Da Huang (Rhubarb) bitter-cold to sweep away pathogenic heat. [Qian Huang] "Didang" means that blood stasis condenses, firmly knots and sticks. Even using Tao Ren Chengqi Tang and various blood-breaking and blood-moving drugs are insufficient to break its hard knotting. Only this sharp drilling nature can withstand it, hence called Didang.
*Zhang Shi Yi Tong* says: If Meng Chong and Shui Zhi are unavailable, replace with Gan Xi Hui (Dry Lacquer Ash).
Note: Didang, Fang Youzhi says: Di means zhi (arrive/reach). It is also the correct treatment that is unchangeable. Yu Jiaoyan, Wang Hu and others agree. Xiju says: Withstanding a great enemy, the four items stand for it. Ke Qin says: Didang means directly reaching the place where it should be attacked.
Taiyang disease with body yellowing, pulse Chen Jie (Deep and Knotted), hardness in the lower abdomen, and dysuria (difficulty urinating) indicates no blood stasis. If urine flows freely, and the person is like mad (delirious/restless), this is a definitive sign of blood syndrome, treat with Didang Tang. (*Qianjin Fang*: "Huang" written as "Zhong"; under "Hard", there is "Man" fullness.)
[Qian Huang] Here, again, through the freeness or obstruction of urine, it distinguishes whether it is a blood syndrome or not. Body yellowing refers to whole-body jaundice. Chen (Deep) indicates interior location, specifically lower jiao. Jie (Knotted) means the pulse comes, moves, then stops; it is a pulse of qi and blood stagnation, unable to continue. Previously it said lower abdomen should be hard and full, here it merely says lower abdomen is hard. With such pulse and symptoms, if there is still dysuria, it ultimately is yellowing caused by damp-heat and blood stasis steaming in the stomach/intestines, not yellowing from blood syndrome. Hence it is said to be no blood. If urine is free and there is delirium, then one knows the pathogenic heat has nothing to do with the Qi level, so qi transformation is not impaired, and the pathogen is in the Yin-Blood. This is jaundice due to blood stasis accumulation. [Ke Qin] Damp-heat remaining in skin and flesh causes yellowing because Wei Qi (Defensive Qi) does not circulate. Dry blood knotted in the Bladder causes yellowing because Ying Qi (Nutritive Qi) is not distributed. Water knotting and Blood knotting are both Bladder diseases, hence both present with lower abdomen hardness/fullness. Dysuria is water knotting; free urination is blood knotting. "Ru" (Like) is a particle. If "Ru" is interpreted literally to distinguish severity from true madness, it is erroneous. [Fang Youzhi] Di (Di) means Shen (Examine/Confirm). It means thus it is confirmed as blood syndrome, leaving no doubt.
Note: For dysuria, Cheng Wuji says: Can use Yinchen Hao Tang (Artemisia Capillaris Decoction). *Buwang Lun* says: Use Wuling San (Five-Ingredient Powder with Poria). Cheng Jiaoqian says: Belongs to Yinchen Wuling San syndrome. Ke Qin says: It is Mahuang Lianqiao Chixiaodou Tang syndrome. Above, select and use appropriately.
Shanghan (Cold Damage) with fever, lower abdominal fullness, should have dysuria, now conversely has free urination, indicating presence of blood stasis. Should purge, do not use other medicines,适宜 (suitable) is Didang Wan (Cochineal and Leech Pill). (Under "You Re" (Has Fever), *Yuhan Jing*, *Maijing*, *Waitai* have "Er" (And) character.)
[Cheng Wuji] Shanghan with fever, lower abdominal fullness, is blood stasis accumulating in the lower jiao. If heat accumulates causing fluids to not flow, then dysuria occurs. If heat does not accumulate fluids, but accumulates blood causing it not to move, and urine is free, this is blood stasis. Should use Tao Ren Chengqi Tang or Didang Tang to purge. However, this case lacks body yellowing, black stools, nor forgetfulness/madness, meaning it has not reached severity. Thus, harsh medicines should not be used. Can use Didang Wan, mild purgation. [Ke Qin] "Has fever" means exterior syndrome still exists.
Formula: Didang Wan (Cochineal and Leech Pill)
Shui Zhi (Leech, Hirudo, 20, roasted ○ Zhou Shenzhai, Wu Qian: 20, roasted in pig fat until black.) Tao Ren (Peach Kernel, Semen Persicae, 25, remove skin and tips ○ *Yuhan Jing*, *Waitai*, Chengben: 30; *Qianjin*: 22; *Qianjin Yi Fang*: has "roasted") Meng Chong (Dragonfly Larva, 20, remove wings and feet, roasted ○ *Yuhan Jing*: 25.) Da Huang (Rhubarb Radix et Rhizoma, 3 liang)
The above four herbs, pound and divide into four pills. Boil one pill in one sheng of water, obtain seven she, take orally. Blood should pass at that time. If not, take again. (*Qianjin*: Make the above four herbs into powder, mix with honey, divide into four pills.)
[Ke Qin] Reduce the dosage, make into pills to slow the action. The formula changes from decoction to pill, but although named pill, it is still boiled as decoction. [Zhang Lu] Boil and take with dregs, same intent as Daxiexiong Tang. Tao Hongjing says: "Shi" (Time) means a cycle, from today morning to tomorrow morning.
Taiyang disease with free urination, due to drinking too much water, must cause palpitations in the epigastrium (Xin Xia); with less urine, must suffer from internal urgency (lower abdominal tension/discomfort). (*Bingyuan* says: Taiyang disease, those with dysuria drink too much water, heart must palpitate etc., this is incorrect.)
[Cheng Wuji] Drinking much water, while urination is free, then water does not accumulate internally, but simply much water in the abdomen causes epigastric palpitations. *Jingui Yaolue* says: Eat little, drink much, water stops in Xin Xia, severe cases then palpitate. Drink much water but dysuria, then water accumulates internally and does not move, must suffer from internal urgency. [Qian Huang] Cold-damage to Stomach, water stops and fails to move immediately, must cause epigastric palpitation. Xin Xia is the region of the Stomach. Ji (Palpitation) is water filling the Stomach, Qi failing to circulate smoothly, leading to trembling/movement. [Cheng Jiaoqian] If urine is little, and desiring water, this is thirst, heat in lower jiao, belongs to Wuling San syndrome. Forcefully giving water, even if no rejection, water accumulates and does not move, must cause internal urgency and fullness. [Wang Hu] Chang Qizhi says: Can use Fuling Jiangzhi Tang (Poria, Ginger, and Licorice Decoction), also Zhuling Tang (Polyporus Decoction). Inferring Chang's intent: Free urination, use Fuling Jiangzhi Tang; Less urine, use Zhuling Tang.