治大便燥结久不通，身体兼羸弱者。
净朴硝（四两） 鲜莱菔（五斤）
将莱菔切片，同朴硝和水煮之。初次煮，用莱菔片一斤，水五斤，煮至莱菔烂熟捞出。就其余汤，再入莱
菔一斤。如此煮五次，约得浓汁一大碗，顿服之。若不能顿服者，先饮一半，停一点钟，再温饮一半，大便即
通。若脉虚甚，不任通下者，加人参数钱，另炖同服。
软坚通结，朴硝之所长也。然其味咸性寒，若遇燥结甚实者，少用之则无效，多用之则咸寒太过，损肺伤
肾。其人或素有劳疾或下元虚寒者，尤非所宜也。惟与莱菔同煎数次，则朴硝之咸味，尽被莱菔提出，莱菔之
汁浆，尽与朴硝融化。夫莱菔味甘，性微温，煨熟食之，善治劳嗽短气（方附水晶桃下），其性能补益可知。
取其汁与朴硝同用，其甘温也，可化朴硝之咸寒，其补益也，可缓朴硝之攻破。若或脉虚不任通下，又借人参
之大力者，以为之扶持保护。然后师有节制，虽猛悍亦可用也。
一媪，年近七旬，伤寒初得，无汗，原是麻黄汤证。因误服桂枝汤，遂成白虎汤证。上焦烦热太甚，闻药
气即呕吐。但饮所煎石膏清水，亦吐。俾用鲜梨片蘸生石膏细末，嚼咽之。约用石膏两半，阳明之大热遂消，
而大便旬日未通，其下焦余热，仍无出路，欲用硝黄降之，闻药气仍然呕吐。且其人素患劳嗽，身体羸弱，过
用咸寒，尤其所忌。为制此方，煎汁一大碗，仍然有朴硝余味，复用莱菔一个，切成细丝，同葱 油醋，和药
汁调作羹。病患食之香美，并不知是药，大便得通而愈。
一媪，年七旬，劳嗽甚剧，饮食化痰涎，不化津液，致大便燥结，十余日不行，饮食渐不能进。亦拟投以
此汤，为羸弱已甚，用人参三钱，另炖汁，和药服之。一剂便通，能进饮食。复俾煎生山药稠汁，调柿霜饼服
之，劳嗽亦见愈。
治疗大便燥结长期不通，且身体兼有消瘦虚弱的患者。
净朴硝（四两） 鲜莱菔（五斤）
将莱菔切成片，与朴硝加水一起煮。第一次煮，用一斤莱菔片，五斤水，煮到莱菔烂熟后捞出。在剩下的汤中，再放入一斤莱菔。这样煮五次，大约能得到浓汁一大碗，一次性服用。如果不能一次性服完，先喝一半，停一个小时，再温热喝另一半，大便就会通畅。如果脉象非常虚弱，不能承受攻下法的，加入人参数钱，单独炖好后同服。
软坚散结、通便导滞，是朴硝的特长。然而它的味道咸、性质寒凉，如果遇到燥结非常严重的情况，用量少则无效，用量多则咸寒太过，损伤肺和肾。那人如果素有劳损疾病或下元虚寒的，尤其不适合使用。只有与莱菔同煎多次，朴硝的咸味就会被莱菔完全提取出来，莱菔的汁液就会与朴硝完全融合。莱菔味甘，性质微温，烤熟吃，善于治疗劳嗽短气（方剂附在水晶桃条目下），其补益的功效可以知道。取它的汁液与朴硝同用，它的甘温之性，可以化解朴硝的咸寒，它的补益作用，可以缓和朴硝的攻破之力。如果脉象虚弱不能承受攻下法，又借助人参的大力，来扶持保护正气。然后像军队一样有节制，虽然猛烈强悍也可以使用。
一位老妇人，年龄接近七十岁，刚得伤寒，无汗，本来是麻黄汤证。因为误服桂枝汤，于是变成了白虎汤证。上焦烦热太严重，闻到药气就呕吐。只喝煎好的石膏清水，也吐。让用鲜梨片蘸生石膏细末，咀嚼咽下。大约用了半两石膏，阳明经的大热随即消退，但大便十天未通，下焦的余热，仍然没有出路，想用硝黄（芒硝、大黄）降火通便，闻到药气仍然呕吐。而且那人素患劳嗽，身体消瘦虚弱，过度使用咸寒药物，更是禁忌。为此配制此方，煎汁一大碗，仍然有朴硝的余味，又用一个莱菔，切成细丝，同葱、油、醋，和药汁调成羹汤。病患吃了觉得香美，并不知道是药，大便通畅而痊愈。
一位老妇人，年龄七十岁，劳嗽非常严重，饮食化为痰涎，不化为津液，导致大便燥结，十多天不通，饮食逐渐不能进食。也打算投以此汤，因为身体已经极度虚弱，用人参三钱，单独炖汁，和药一起服用。一剂药后大便通畅，能进食了。又让煎生山药稠汁，调柿霜饼服用，劳嗽也见好转。
Treatment for chronic constipation with dry, hard stools and concomitant emaciation and weakness.
Purified Natrii Sulfas (Jing Puxiao) (4 liang)
Fresh Radish (Xian Lifu) (5 jin)
Slice the fresh radishes and boil them together with Natrii Sulfas in water. For the first boiling, use one jin of radish slices and five jin of water; boil until the radishes are soft and cooked through, then remove them. To the remaining decoction, add another jin of radishes. Repeat this process five times. Approximately one large bowl of concentrated juice will be obtained. Administer orally in a single dose. If the patient cannot consume it all at once, drink half first, wait for one hour, then warm and drink the remaining half. The bowels will then move freely. If the pulse is extremely deficient and the patient cannot tolerate purgation, add several qian of Ginseng Radix et Rhizoma (Renshen), decocted separately, and take it together with the main decoction.
The strength of Natrii Sulfas lies in its ability to soften hardness and unblock accumulation. However, its flavor is salty and its nature is cold. In cases of severe dryness and accumulation, a small dose is ineffective, while a large dose causes excessive cold and saltiness, damaging the Lung and Kidney. It is particularly unsuitable for patients who have a history of consumptive diseases or deficiency-cold in the lower origin. Only by decocting it multiple times with radishes can the salty flavor of Natrii Sulfas be fully extracted by the radish, allowing the radish's juice to thoroughly merge with the Natrii Sulfas. Radish has a sweet flavor and a slightly warm nature; when roasted and eaten, it effectively treats consumptive cough and shortness of breath (formula attached under Shuijing Tao). Its nourishing properties are evident. Using its juice together with Natrii Sulfas, its sweet-warm nature can transform the salty-cold property of Natrii Sulfas, and its nourishing action can moderate the attacking and breaking force of Natrii Sulfas. If the pulse is deficient and purgation is not tolerated, the strong support of Ginseng Radix et Rhizoma is borrowed to protect and sustain the healthy qi. Thus, with proper regulation and restraint, even potent and fierce herbs can be used safely.
An elderly woman, nearly seventy years old, contracted Cold Damage initially. She had no sweating, which was originally an indication for Mahuang Tang (Ephedra Decoction). Due to the mistaken administration of Guizhi Tang (Cinnamon Twig Decoction), her condition transformed into a Baihu Tang (White Tiger Decoction) pattern. There was extreme heat and irritability in the upper jiao, causing vomiting upon smelling any medicine. Even drinking the clear water from decocted Gypsum Fibrosum (Shigao) caused vomiting. I instructed her to chew and swallow raw Gypsum Fibrosum powder dipped in fresh pear slices. Approximately half a liang of Gypsum Fibrosum was used, and the intense heat of the Yangming channel subsided. However, her bowels had not moved for ten days, and the residual heat in the lower jiao still had no outlet. Attempting to use Xiaoshi (Mangxiao, Natrii Sulfas) and Dahuang (Rhei Radix et Rhizoma) to descend the heat again triggered vomiting upon smelling the medicine. Moreover, she suffered from chronic consumptive cough and was physically emaciated; excessive use of salty-cold herbs was strictly contraindicated. Therefore, I formulated this prescription. The decoction yielded one large bowl but retained a salty aftertaste from Natrii Sulfas. I took another radish, cut it into fine shreds, and mixed it with scallion, oil, and vinegar to create a soup with the medicinal juice. The patient ate it finding it delicious, unaware it was medicine. Her bowels moved freely, and she recovered.
Another elderly woman, aged seventy, suffered from severe consumptive cough. Her diet transformed into phlegm-saliva rather than body fluids, leading to dry, hard stool that remained unpassed for over ten days. Her food intake gradually decreased. I intended to administer this same decoction. However, due to her extreme emaciation, I added three qian of Ginseng Radix et Rhizoma, decocted separately, and mixed the juice with the medicine. After one dose, her bowels moved, and she could eat. Subsequently, I instructed her to decoct Dioscoreae Rhizoma (Shanyao) to a thick consistency, mix it with persimmon frost cakes, and take them. Her consumptive cough also showed improvement.