茯苓，味甘、淡，气平，降也，阳中阴也，无毒。有赤、白二种，白者佳，亦可用入心、
脾
、肺、肝、肾五脏，兼入膀胱、大小肠、膻中、胃经。助阳，利窍通便，不走精气，利血仅
在腰脐，除湿行水，养神益智，生津液，暖脾，去痰火，益肺，和魂练魄，开胃浓肠，却惊
痫，安胎孕，久服耐老延年。
茯神，即茯苓之一种。但茯神抱松木之根而生者也，犹有顾本之义，故善补心气，止恍
惚惊
悸，尤治善忘，其余功用，与茯苓相同，此二种，利中有补，久暂俱可用也，可君可臣，
而
又可佐使。惟轻重之宜分，无损益之可论。或谓汗多而阴虚者宜忌，少用之何损哉。或言小
便素利者勿服，恐助燥损阴，微用之何
妨。初病与久病相殊，而健脾正宜于久病，何必尽去夫茯苓也。丹溪曰∶茯苓有行水之能，
久服损人。八味丸用之，亦不过接引诸药，归就肾经，去胞中积陈，而以为搬运之功也。夫
八味丸有桂、附、熟地、山萸之直入于肾，何藉茯苓之引经耶。仲景张夫子用茯苓于八味丸
中，大有深意。以熟地纯阴，而性过于腻滞，虽泽泻利水，熟地之滋润已足相制，然而泽泻
过于利水，未必健脾以去湿。故亦用茯苓以佐之，利腰脐而又不走气，使泽泻亦不过于渗泄
，则泻中有补，助熟地、山药、山茱速于生阴，实非徒为接引而用之也。
或问茯苓健脾，而张仲景公用之益肾，意者脾肾同治耶？夫茯苓虽亦入脾，而张夫子用
之全
非取其健脾，止取其益肾耳，夫肾恶燥，而亦恶湿，过燥则水干，而火易炽，过湿则邪住，
而精难生。用茯苓于六味丸中，泻肾中之邪水，以补肾中之真水也，故与健脾之意全不相干
，勿认作脾肾同治也。
或问茯苓不健脾而益肾，而茯苓实健脾之物也，意者肾健而脾亦健乎？夫肾健而脾亦健，
此
六味汤之功用也。茯苓只能益肾以通胃耳，胃为肾之关门，肾气足而关门旺，不可单归功于
茯苓也。然而，茯苓之气实先通于胃。夫茯苓下利之物，如何能上行于胃。不知茯苓尤通上
下之窍，而胃亦是水谷之海，利水而水不入海，将何注乎。故下通膀胱，而上通于胃，胃气
得肾气之升腾，而胃气有不更开，饮食有不更进乎。似乎脾健而能容，实亦胃健而能受焉也
。
或疑茯苓、泽泻，同是利水之物，而或言过于利水，或言未能健脾，皆是与人相反，谓
先生
不好奇得乎？曰∶非好奇也。二味实各有功用，不得不分言之耳。泽泻，泻之中有补，表其
补之功，则其泻正可用也；茯苓，补中有泻，论其泻之益，则其补亦可用也。凡药有功有过
，明辨功过于胸中，自然临症无
差也。
或问六味丸中阐发已尽，不识茯苓于前说之外，尚有异论乎？前说不足以尽茯苓之义也。
仲
景
夫子用茯苓于六味丸中也，岂特泻肾中之邪水，以补肾中之真水哉。茯苓更能入肾，以通肾
中之火气。肾中火气，上通胃而下通膀胱二经。苟无肾火之气以相通，则上水不能入，而下
水不能出矣。上水不能入者，非不能饮也，饮水而水之气不消；下水不能出者，非不能容，
而水之气不泄不消，而水势必奔迫于中焦，而不能化矣，惟有火气以相通，而上下之水始周
流
而无滞。六味补肾中之水，而不补肾中之火，则火不能自通于胃与膀胱矣。得茯苓代为宣化
，而上下之水得行，何致有不消不泄之虑哉。茯苓用之于六味丸中者，尚有如此妙义也。
又问茯苓用之于六味丸中，奇义如此，而用之于八味丸中，亦别有意义乎？曰∶有。茯
苓泻
水，亦能泻火。泻水者泻肾中之邪水，则泻火者独不泻肾中之邪火乎。八味丸用桂、附以补
火者，补肾中之真火也。然补肾中之真火，而肾中之邪火不去，则真火不生，反助邪火而上
升矣。仲景夫子用茯苓于八味丸中，正取其泻邪火以补真火也。桂、附得茯苓之助，无邪火
之相干，自然真火之速长。于是火生而脾土得其益，受水谷而能容，胃土得其益，进饮食而
无碍，肺气调，而心气降、肝气平矣。
又问茯苓用之四君子汤与六君子汤，似非尽利水也，何独不言其奇乎？夫茯苓用之于阴
药之
内，可以出奇。茯苓用之于阳药之间，无以显异，不过佐人参、白术，分消其水湿，以固其
脾土而开胃气也。
又问茯苓用之于都气丸中，亦未见出奇，必得肉桂，而后泻水，安在入肾气丸中即能出
奇乎
？曰∶肾气丸之妙，全在茯苓。茯苓利水，人人知之。利水之中，得群阴之助，更能于补水
中，以行其利水之权；得二阳之助，更能于补火之中，以全其化水之神。止利其邪水，而不
使波涛泛溢，又不损其真水，而转使热气薰蒸，通上下三焦，消内外二湿，皆茯苓为君之功
也。倘以茯苓为臣，而君以熟地，势必中焦阻滞，水积于皮肤而不得直入于膀胱矣，又何以
泻之哉。
或问夏子益集奇异治病之方，有人十指节断坏，惟有筋连无节肉，虫出如灯心，长数寸，
遍
身绿毛，以茯苓、胡黄连，煎饮而愈，岂亦有义乎？曰∶是湿热出虫耳。茯苓以去湿，黄连
以解热，湿热散而虫自死矣。惟是虫身长绿毛，实有秘义。此人必手弄青蛙，戏于池塘之中
，绿毛之龟在池内，欲吞之而不可得，故气冲而手，久之而手烂，得至阴之毒而不散，故皮
烂而肉腐，生长虫绿毛也。惜吾发异议，无人证之耳。
或问今人用茯苓，多用人乳浸泡，久制则白色变红，其有益于人乎？夫补药而用茯苓者，
恐
纯补之脏滞，故用之通达，使于泻之中，以助其补之力也，若过用乳制，则通利之性全失，
一味呆补，反不能佐补药以成功。此近人不知用药之功，而妄为制变，不可以为法也。
茯苓，味甘、淡，气平，具有沉降之性，属阳中之阴，无毒。有赤、白两种，白色者佳，也可入心、脾、肺、肝、肾五脏，兼入膀胱、大肠、小肠、膻中（心包络）、胃经。能助阳，利窍通便，不耗散精气，活血作用仅在腰脐部位，除湿行水，养神益智，生津液，暖脾，去痰火，益肺，和魂练魄，开胃浓肠，治惊痫，安胎孕，久服可耐老延年。
茯神，是茯苓的一种。但茯神是抱着松木根而生的，还有顾本的意义，所以善于补心气，止恍惚惊悸，尤其治疗健忘，其余功用，与茯苓相同，这两种药，利中有补，久用暂用都可以使用，可做君药、臣药，又可做佐使药。只是轻重应当区分，没有损益可以议论。有人说汗多而阴虚者宜忌，少用有什么损害呢？有人说小便平时通利者勿服，恐怕助燥损阴，微用又有什么妨碍呢？初病与久病不同，而健脾正适宜于久病，何必完全去掉茯苓呢？丹溪说：茯苓有行水的能力，久服损人。八味丸（金匮肾气丸）用它，也不过是接引诸药，归就肾经，去除胞中积陈，而作为搬运之功。八味丸有桂枝、附子、熟地黄、山茱萸直入于肾，何需借茯苓来引经呢？张仲景在八味丸中使用茯苓，大有深意。因为熟地黄纯阴，而性质过于腻滞，虽然泽泻利水，熟地黄的滋润已足以相制，然而泽泻过于利水，未必能健脾以去湿。所以也用茯苓来辅助它，利腰脐而不走气，使泽泻也不至于过于渗泄，则泻中有补，帮助熟地黄、山药、山茱萸速于生阴，实在不是为了徒然作为接引而使用的。
有人问茯苓健脾，而张仲景用它来益肾，意思是脾肾同治吗？茯苓虽然也入脾，但张仲景用它完全不是取其健脾，只是取其益肾罢了。肾恶燥，也恶湿，过燥则水干，而火易炽盛，过湿则邪停留，而精难生。在六味丸中使用茯苓，是泻肾中的邪水，以补肾中的真水，所以与健脾的意思全不相干，不要认作脾肾同治。
有人问茯苓不健脾而益肾，但茯苓确实是健脾的药物，意思是肾健而脾也健吗？肾健而脾也健，这是六味丸的功用。茯苓只能益肾以通胃而已，胃为肾的关门，肾气足而关门旺，不能单归功于茯苓。然而，茯苓之气确实先通于胃。茯苓是下利的药物，怎么能上行于胃呢？不知道茯苓尤其通上下之窍，而胃也是水谷之海，利水而水不入海，将流向哪里呢？所以下通膀胱，而上通于胃，胃气得肾气的升腾，而胃气能不更开，饮食能不更进吗？似乎脾健而能容，实则是胃健而能受。
有人怀疑茯苓、泽泻，同样是利水的药物，有人说过于利水，有人说未能健脾，都是与人相反，说先生不好奇吗？回答说：不是好奇。这两味药确实各有功用，不得不分别论述。泽泻，泻中有补，表彰其补的功效，那么它的泻正是可用的；茯苓，补中有泻，论及其泻的益处，那么它的补也是可用的。凡药有功有过，明辨功过于胸中，自然临症无差错。
有人问六味丸中的道理阐发已尽，不知茯苓在前说之外，还有异论吗？前说不足以尽茯苓之义。张仲景在六味丸中使用茯苓，岂只是泻肾中的邪水，以补肾中的真水吗？茯苓更能入肾，以通肾中的火气。肾中火气，上通胃而下通膀胱二经。如果没有肾火之气相通，则上水不能入，而下水不能出。上水不能入，不是不能饮，而是饮水后水的气不能消；下水不能出，不是不能容，而是水的气不能泄不能消，而水势必奔迫于中焦，而不能化。只有有火气相通，而上下之水才周流而无滞。六味丸补肾中的水，而不补肾中的火，则火不能自通于胃与膀胱。得茯苓代为宣化，而上下之水得以运行，何致有不消不泄的忧虑呢？茯苓用在六味丸中，尚有如此妙义。
又问茯苓用在六味丸中，奇义如此，而用在八味丸中，也有别有意义吗？回答说：有。茯苓泻水，也能泻火。泻水是泻肾中的邪水，那么泻火难道不也是泻肾中的邪火吗？八味丸用桂枝、附子来补火，是补肾中的真火。然而补肾中的真火，而肾中的邪火不去，则真火不生，反而助邪火而上升。张仲景在八味丸中使用茯苓，正是取其泻邪火以补真火。桂枝、附子得茯苓的帮助，无邪火相干扰，自然真火迅速生长。于是火生而脾土得其益，受水谷而能容，胃土得其益，进饮食而无碍，肺气调，而心气降、肝气平。
又问茯苓用在四君子汤与六君子汤中，似乎不全是为了利水，为何独不言其奇呢？茯苓用在阴药之内，可以出奇。茯苓用在阳药之间，无以显异，不过是佐助人参、白术，分消其水湿，以固其脾土而开胃气。
又问茯苓用在都气丸中，也未见出奇，必得肉桂，而后泻水，怎么进入肾气丸中就能出奇呢？回答说：肾气丸的妙处，全在茯苓。茯苓利水，人人皆知。利水之中，得群阴之助，更能于补水中，以行其利水之权；得二阳之助，更能于补火之中，以全其化水之神。只利其邪水，而不使波涛泛溢，又不损其真水，而转使热气薰蒸，通上下三焦，消内外二湿，都是茯苓为君药的功劳。如果把茯苓作为臣药，而以熟地黄为君药，势必中焦阻滞，水积于皮肤而不得直入于膀胱，又何以泻之呢？
有人问夏子益集奇异治病之方，有人十指节断坏，惟有筋连无节肉，虫出如灯心，长数寸，遍身绿毛，用茯苓、胡黄连，煎饮而愈，难道也有意义吗？回答说：这是湿热出虫。茯苓以去湿，黄连以解热，湿热散而虫自死。只是虫身长绿毛，实有秘义。此人必定手弄青蛙，戏于池塘之中，绿毛之龟在池内，欲吞之而不可得，故气冲而手，久之而手烂，得至阴之毒而不散，故皮烂而肉腐，生长虫绿毛。可惜我发表异议，无人证实。
有人问今人用茯苓，多用人乳浸泡，久制则白色变红，这对人有益吗？补药而用茯苓，恐怕纯补导致脏滞，所以用之通达，使于泻之中，以助其补之力。如果过用乳制，则通利之性全失，一味呆补，反不能佐补药以成功。这是近人不知用药之功，而妄为制变，不可以为法。
Poria (Fuling), sweet and bland in flavor, neutral in nature, descending, yin within yang, non-toxic. There are two types: red and white, with the white being superior. It enters the five zang organs of the Heart, Spleen, Lung, Liver, and Kidney, and also connects to the Bladder, Large Intestine, Small Intestine, Danzhong (Pericardium), and Stomach meridians. It assists Yang, benefits orifices, unblocks bowels, does not dissipate essence and qi, its blood-invigorating action is limited to the waist and umbilicus, removes dampness and promotes water metabolism, nourishes the spirit and enhances intelligence, generates body fluids, warms the Spleen, eliminates phlegm-heat, benefits the Lung, harmonizes the Hun and refines the Po, opens the appetite and thickens the intestines, treats epilepsy and convulsions, calms the fetus, and long-term use promotes longevity and anti-aging.
Fushen (Poria with Hostwood) is a type of Poria. However, Fushen grows embracing the roots of pine trees, retaining the meaning of remembering one's roots; thus, it is particularly effective in tonifying Heart Qi, stopping dizziness and palpitations, and especially treating forgetfulness. Its other functions are identical to those of Poria. Both herbs possess the characteristic of promoting drainage while providing tonification, making them suitable for both short-term and long-term use. They can serve as Sovereign (Jun), Minister (Chen), Assistant (Zuo), or Envoy (Shi) herbs. Only their dosage weights need differentiation; there is no debate regarding their beneficial or harmful effects. Some say they should be avoided in cases of excessive sweating and Yin deficiency; what harm is there in using a small dose? Others say they should not be taken by those whose urination is normally clear and frequent, fearing they may aggravate dryness and damage Yin; what objection is there to using a slight dose? Acute illness differs from chronic illness, and strengthening the Spleen is precisely suitable for chronic conditions; why completely eliminate Poria? Danxi stated: "Poria has the ability to promote water metabolism; long-term use damages the person." In Ba Wei Wan (Eight-Ingredient Pill with Rehmannia), it is used merely to guide other herbs into the Kidney meridian, remove accumulated stagnation in the uterus, and serve a transport function. Ba Wei Wan contains Cinnamon Twig (Guizhi), Aconite Root (Fuzi), Prepared Rehmannia Root (Shudihuang), and Cornus Fruit (Shanzhuyu) which directly enter the Kidney; why rely on Poria for meridian guidance? Zhang Zhongjing's use of Poria in Ba Wei Wan holds profound significance. Since Prepared Rehmannia is purely Yin and its nature is overly cloying and stagnant, although Alisma Rhizome (Zexie) promotes water metabolism, the moistening effect of Prepared Rehmannia is sufficient to counteract it. However, Alisma is too draining and may not effectively strengthen the Spleen to resolve dampness. Therefore, Poria is also used to assist it; it benefits the waist and umbilicus without dispersing Qi, ensuring that Alisma does not drain excessively. Thus, draining contains tonification, assisting Prepared Rehmannia, Chinese Yam (Shanyao), and Cornus Fruit in rapidly generating Yin. It is certainly not used merely for guiding purposes.
One asks: Poria strengthens the Spleen, yet Zhang Zhongjing uses it to benefit the Kidney; does this imply simultaneous treatment of the Spleen and Kidney? Although Poria enters the Spleen, Zhang Zhongjing’s use of it is entirely not for strengthening the Spleen, but solely for benefiting the Kidney. The Kidney dislikes dryness but also dislikes dampness. Excessive dryness leads to fluid depletion and easy flare-up of Fire; excessive dampness causes pathogenic retention and difficulty in generating Essence. In Liu Wei Wan (Six-Ingredient Pill with Rehmannia), Poria is used to drain evil water from the Kidney to tonify true water within the Kidney. Therefore, it has nothing to do with strengthening the Spleen; do not mistake it for simultaneous Spleen-Kidney treatment.
One asks: If Poria does not strengthen the Spleen but benefits the Kidney, yet Poria is indeed a substance that strengthens the Spleen, does this mean that when the Kidney is healthy, the Spleen is also healthy? That the Kidney is healthy and the Spleen is also healthy is the function of Liu Wei Wan. Poria can only benefit the Kidney to open the Stomach. The Stomach is the gatekeeper of the Kidney; when Kidney Qi is sufficient, the gatekeeper is vigorous. This cannot be attributed solely to Poria. However, the Qi of Poria indeed first communicates with the Stomach. Poria is a downward-draining herb; how can it ascend to the Stomach? One must understand that Poria particularly opens the orifices of the upper and lower parts. The Stomach is also the sea of water and grain. If water is drained but does not enter the sea, where will it flow? Thus, it drains downward to the Bladder and opens upward to the Stomach. When Stomach Qi receives the ascending vapor of Kidney Qi, will Stomach Qi not open further, and will food intake not increase? It seems that a healthy Spleen allows containment, but actually, it is a healthy Stomach that allows reception.
One doubts: Poria and Alisma are both water-draining substances. Some say Alisma is too draining, others say Poria fails to strengthen the Spleen. These views contradict each other. Do you claim novelty, Master? I reply: It is not about novelty. These two herbs truly have distinct functions and must be discussed separately. Alisma: within draining lies tonification; highlighting its tonifying merit shows its draining action is useful. Poria: within tonification lies draining; discussing the benefit of its draining shows its tonifying action is also useful. All herbs have merits and faults. Clearly distinguishing merits and faults in one’s mind ensures no errors in clinical practice.
One asks: The principles in Liu Wei Wan have been fully expounded. Are there other theories regarding Poria beyond the previous discussion? The previous discussion is insufficient to exhaust the meaning of Poria. When Zhang Zhongjing used Poria in Liu Wei Wan, did he merely drain evil water from the Kidney to tonify true water? Poria can further enter the Kidney to communicate the Fire Qi within the Kidney. Kidney Fire Qi communicates upward to the Stomach and downward to the Bladder meridians. Without the communication of Kidney Fire Qi, upper water cannot enter, and lower water cannot exit. Upper water not entering does not mean inability to drink, but rather that the Qi of ingested water fails to transform. Lower water not exiting does not mean inability to hold, but rather that the Qi of water fails to excrete and transform, causing water to surge in the Middle Jiao and fail to metabolize. Only with Fire Qi communication can upper and lower waters circulate freely without stagnation. Liu Wei Wan tonifies Kidney Water but does not tonify Kidney Fire; thus, Fire cannot spontaneously communicate with the Stomach and Bladder. With Poria acting as an agent for dissemination and transformation, upper and lower waters can move. Why worry about failure to transform or excrete? The use of Poria in Liu Wei Wan holds such subtle meanings.
Another question: Poria has such奇 (extraordinary) meanings in Liu Wei Wan; does its use in Ba Wei Wan also carry different significance? I reply: Yes. Poria drains water and can also drain Fire. Draining water refers to draining evil water from the Kidney; does draining Fire not refer to draining evil Fire from the Kidney? Ba Wei Wan uses Cinnamon Twig and Aconite to tonify Fire, specifically tonifying true Fire in the Kidney. However, if true Fire in the Kidney is tonified while evil Fire remains, true Fire will not generate; instead, it will exacerbate evil Fire and cause it to ascend. Zhang Zhongjing’s use of Poria in Ba Wei Wan precisely aims to drain evil Fire to support true Fire. With the assistance of Poria, Cinnamon Twig and Aconite are free from interference by evil Fire, allowing true Fire to grow rapidly. Consequently, Fire generation benefits Spleen Earth, enabling it to receive water and grain; Stomach Earth benefits, allowing dietary intake without obstruction; Lung Qi regulates, Heart Qi descends, and Liver Qi levels out.
Another question: Poria’s use in Si Jun Zi Tang (Four Gentlemen Decoction) and Liu Jun Zi Tang (Six Gentlemen Decoction) seems not primarily for water drainage. Why not speak of its extraordinariness here? When Poria is used within Yin-tonifying formulas, it can produce extraordinary effects. When used among Yang-tonifying herbs, its uniqueness is less apparent; it merely assists Ginseng Radix (Renshen) and Atractylodes Rhizome (Baizhu) to distribute and eliminate dampness, thereby consolidating Spleen Earth and opening Stomach Qi.
Another question: Poria’s use in Du Qi Wan (Duqi Pill) does not seem extraordinary either. It requires Cinnamon Bark (Rougui) to drain water. How can it be considered extraordinary when entering Shen Qi Wan (Kidney Qi Pill)? I reply: The wonder of Shen Qi Wan lies entirely in Poria. Everyone knows Poria promotes water metabolism. Within water drainage, aided by a group of Yin herbs, it can better exercise its authority to drain water during water tonification; aided by two Yang herbs, it can better complete its divine power to transform water during Fire tonification. It drains only evil water without causing turbulent overflow, and does not damage true water but instead transforms heat to steam, communicating the Upper, Middle, and Lower Jiao, and eliminating internal and external dampness. All these are the merits of Poria as the Sovereign herb. If Poria were made a Minister herb and Prepared Rehmannia the Sovereign, stagnation in the Middle Jiao would inevitably occur, water would accumulate in the skin and fail to enter the Bladder directly, and how could it be drained?
One asks: Xia Ziyi collected strange prescriptions for curing diseases. There was a case where a person’s ten finger joints were broken and damaged, connected only by tendons without joint flesh, worms emerged like rush pith, several inches long, covered in green hair all over the body. He was cured by decocting and drinking Poria and Picrorhiza Rhizome (Huhuanglian). Does this also have meaning? I reply: This is worms caused by Damp-Heat. Poria removes dampness, Huanglian (Coptis Rhizome) clears heat. When Damp-Heat scatters, the worms die naturally. However, the green hair on the worm bodies holds a secret meaning. This person likely played with frogs in a pond. A turtle with green hair in the pond tried to swallow the frog but failed. Thus, Qi rushed to the hand, causing rotting over time. The extreme Yin toxin entered but did not disperse, causing skin decay and flesh corruption, leading to the growth of worms with green hair. Unfortunately, I raised this dissenting view, but no one verified it.
One asks: Nowadays, people often soak Poria in human milk. Long processing turns the white color red. Is this beneficial to humans? When using Poria in tonifying medicines, it is feared that pure tonification may cause organ stagnation; thus, Poria is used to ensure smooth circulation, aiding tonification through draining. If processed excessively with milk, its draining and unblocking nature is completely lost. It becomes a rigid tonification, failing to assist tonifying medicines to achieve success. This reflects modern ignorance of the efficacy of herbs and reckless alteration of processing methods, which should not be followed as a standard.