〔害〕扁鹊云∶多服令人眼昏，凡病患无湿无饮，而阴虚及肾气乏绝，阳衰精自流，肾
气不
固，精滑目痛，虚寒作泄等症，法咸禁用。以其淡渗利水，久服则降令太过，清气不升，真
阴潜耗，安得不病目耶？
〔利〕甘咸微寒，通肾膀胱水道，善去胞胎，能止泄精。
〔修治〕八月采根，不计多少，细锉酒浸一宿，取出曝干，任用。
（见脾部）
〔害〕见心部补阵茯神条下。
〔利〕甘淡平，泻肾小肠膀胱湿热，功同茯苓而稍逊，利水偏长。
〔修治〕大山山谷大松下附根而生，二八月采，掘取阴干。凡用皮去心，捣细，于水盆
中搅
浊，浮者滤去之，此是茯苓赤筋，若误服饵，令人瞳子并黑睛点小，兼盲目。
（见脾部）
〔害〕生于卤地，刮取煎炼，在底者为朴硝，在上为芒硝，有牙者为马牙硝。置风日中，
消
尽水气，清白如粉，为风化硝。若经甘草水 过，即元明粉。究其功用，无坚不磨，无结不
散，无热不荡，无积不推，可谓直往无前，无留碍之性也。非邪结下焦，坚实不可按者不用
，恐误伐下焦真阴故也。病不由于邪热深固，闭结难通，断勿轻投。至于血涸津液枯竭，以
致大肠燥结，阴虚精乏以致大热，骨蒸火炎于上，以致头痛、目昏、口渴、耳聋、咽痛、吐
血、衄血、虚极类实等症，切戒勿施，庶免虚虚之咎。
〔利〕咸辛微寒，泻肾火，治阳强，能荡三焦肠胃实热，大泻下泄，与大黄功同。破血
攻痰
，软坚消食，又能通经堕胎。
〔修治〕采无时，青白者佳，黄者损人，赤者杀人。
元明粉功缓力少轻，明目清燥，推陈致新。朴硝，即皮硝。朴硝在下最粗而浊，芒硝在上质
稍清，元明粉再经甘草水煎炼，尤为精粹。
【害处】扁鹊说：长期服用会让人眼睛昏花。凡是患者体内没有湿邪和水饮停聚，且存在阴虚、肾气衰竭、阳气衰弱导致精液自行滑泄、肾气不固、精关不守、眼睛疼痛、因虚寒引起的腹泻等症状的，按照法则都应当严禁使用泽泻。因为泽泻味道淡，具有渗湿利水的作用，长期服用会导致降泄作用过强，清气不能上升，真阴暗中消耗，怎么能不导致眼病呢？
【功效】味甘、咸，性微寒，能疏通肾脏和膀胱的水道，善于消除胞胎（此处指瘀血或病理产物），能够制止遗精。
【炮制方法】八月采集根部，数量不限，切成细丝后用酒浸泡一夜，取出晒干，即可随意使用。
（参见脾部）
【害处】参见心部补益方阵中茯神条目下的内容。
【功效】味甘、淡，性平，能清泻肾脏、小肠和膀胱的湿热，功效与茯苓相同但稍弱，在利水方面特长。
【炮制方法】生长在大山深谷的大松树旁并依附树根而生，二月和八月采集，挖掘出来阴干。凡是用茯苓时要去掉外皮和中心部分，捣碎成细末，放入水盆中搅拌使浑浊物沉淀，浮起的部分过滤去除，这是茯苓的赤色筋脉，如果误服，会导致瞳孔和黑睛出现黑点，甚至引起失明。
（参见脾部）
【害处】生长在盐碱地，刮取后煎炼而成，沉在底部的称为朴硝，在上层的称为芒硝，有棱角的称为马牙硝。放置在风和日光下，蒸发尽水分，变得清白如粉，称为风化硝。如果用甘草水处理过，就是元明粉。究其功用，没有什么坚硬不能磨碎的，没有什么结滞不能消散的，没有什么热邪不能清除的，没有什么积滞不能推荡的，可以说是勇往直前，没有阻碍的性质。如果不是下焦有邪气结聚，坚硬结实且不可按压的情况，就不使用，恐怕会错误地损伤下焦的真阴。如果疾病不是由于邪热深重坚固、闭塞结滞难以通畅引起的，千万不要轻易投用。至于血液枯竭、津液干涸导致大肠燥结，阴虚精乏导致大热，骨蒸潮热如火炎上，导致头痛、眼睛昏花、口渴、耳聋、咽喉疼痛、吐血、鼻出血、极度虚弱却表现出类似实证的症状等，务必戒除不要施用，以免犯“虚虚”（使虚者更虚）的错误。
【功效】味咸、辛，性微寒，能清泻肾火，治疗阳强不倒，能荡涤三焦和肠胃的实热，大力泻下排泄，功效与大黄相同。能破血攻痰，软化坚积消食，又能通经堕胎。
【炮制方法】采集没有固定时间，以青色白色为佳，黄色的损害人体，红色的会致人死亡。
元明粉功效缓和，力量较轻，能明目清燥，推陈出新。朴硝，即皮硝。朴硝在下层最粗浊，芒硝在上层质地稍清，元明粉再经过甘草水处理煎炼，尤为精粹。
[Harm] Bian Que said: Long-term use causes blurred vision. For patients without dampness or fluid retention, but presenting with Yin deficiency, exhaustion of Kidney Qi, Yang decline leading to spontaneous seminal emission, insecure Kidney Qi, spermatorrhea, eye pain, and diarrhea due to deficiency-cold, it is strictly contraindicated according to the principles. This is because its light and penetrating nature promotes urination; prolonged use leads to excessive descending action, preventing clear Qi from ascending, and secretly depleting True Yin. How can one not suffer from eye diseases?
[Benefit] Sweet, salty, slightly cold in nature. It unblocks the water pathways of the Kidney and Bladder, effectively eliminating pathogenic factors in the uterus (or resolving blood stasis), and can stop seminal emission.
[Processing] Harvest the roots in August, regardless of quantity. Cut into fine shreds, soak in wine overnight, take out, dry in the sun, and use as needed.
(See Spleen Section)
[Harm] See the entry for Fushen (Poria with Hostwood) under the Tonifying Array in the Heart Section.
[Benefit] Sweet, bland, neutral in nature. It drains damp-heat from the Kidney, Small Intestine, and Bladder. Its efficacy is similar to Poria (Fuling) but slightly weaker, with a particular strength in promoting urination.
[Processing] Grows attached to the roots of large pines in deep valleys of great mountains. Harvest in the second and eighth lunar months. Dig up and dry in the shade. When used, remove the outer skin and the core, grind into fine powder. Stir in a basin of water; filter off the floating impurities, which are the red sinews of Poria. If mistakenly ingested, it causes black spots on the pupil and cornea, and may lead to blindness.
(See Spleen Section)
[Harm] Grows in saline lands. Scraped and refined; the substance settling at the bottom is called Pu Xiao (Mirabilite crude), that at the top is Mang Xiao (Mirabilite refined), and those with crystalline edges are Ma Ya Xiao (Horse-tooth Mirabilite). Placed in wind and sunlight to evaporate moisture until white and powdery, it becomes Feng Hua Xiao (Effloresced Mirabilite). If processed with licorice water, it becomes Yuan Ming Fen (Refined Mirabilite). Its function is such that nothing hard is not ground down, no accumulation is not dispersed, no heat is not cleared, and no stagnation is not pushed away. It moves forward without obstruction. It should not be used unless there is a firm, pressing-hard accumulation of pathogenic factors in the Lower Jiao, lest it erroneously damage the True Yin of the Lower Jiao. If the disease is not caused by deep-seated, solidified pathogenic heat leading to severe constipation and blockage, do not administer lightly. Regarding cases where blood is exhausted and body fluids dried up causing dry constipation of the Large Intestine, or Yin deficiency and essence depletion causing high fever, bone-steaming tidal fever rising like fire causing headache, blurred vision, thirst, deafness, sore throat, hematemesis, epistaxis, and extreme deficiency mimicking excess syndromes, these must be strictly avoided to prevent the error of "depleting the deficient."
[Benefit] Salty, acrid, slightly cold in nature. It clears Kidney Fire, treats priapism, and can purge excess heat from the San Jiao and intestines/stomach, inducing strong purgation. Its effect is similar to Da Huang (Rhubarb Root and Rhizome). It breaks blood stasis, attacks phlegm, softens hardness, aids digestion, and can unblock menstruation and induce abortion.
[Processing] Harvesting time is unrestricted. Greenish-white specimens are best; yellow ones harm the body, and red ones are fatal.
Yuan Ming Fen has a milder effect and lighter power; it brightens the eyes and clears dryness, pushing out the old to generate the new. Pu Xiao is also known as Pi Xiao. Pu Xiao settles at the bottom and is coarsest and most turbid; Mang Xiao rises to the top and is clearer in texture; Yuan Ming Fen, after further processing with licorice water, is the most refined.