熟地，味甘，性温，沉也，阴中之阳，无毒。入肝肾二经。生血益精，长骨中脑中之髓。
真
阴之气非此不生，虚火之焰非此不降。洵夺命之神品，延龄之妙味也。世人以其腻滞，弃而
不用，亦未知其功效耳。夫肾有补而无泻，是肾必宜补矣。然而补肾之药，正苦无多。山茱
萸、牛膝、杜仲、北五味之外，舍熟地又用何药哉。况山茱萸、牛膝不可为君，而杜仲又性
过于温，可以补肾火之衰，而不可补肾水之乏。此熟地之必宜用也。熟地系君药，可由一两
以用至八两。盖补阴之药与补阳之药，用之实有不同。补阳之药，可少用以奏功，而补阴之
药，必多用以取效。以阳主升而阴主降。阳升，少用阳药而气易上腾。阴降，少用阴药而味
难下达。熟地至阴之药，尤与他阴药有殊，非多用之，奚以取胜。或谓熟地至阴之药，但其
性甚滞，多用之而腻膈生痰，万一助痰以生喘，亦甚可危也。此正不知熟地之功力也。自神
农尝草之后，将此味失谈，遂使后世不知其故。虽历代名医多有发明，而亦未尝言其秘奥。
夫熟地岂特不生痰，且能消痰，岂特不滞气，且善行气，顾人用之何如耳。夫痰有五脏之异
。痰出脾、肺者，用熟地则助其湿，用之似乎不宜。倘痰出于心、肝、肾者，舍熟地又何以
逐之耶。故人有吐痰如清水者，用二陈消痰化痰之药，百无成功，乃服八味汤，而痰气之汹
涌者顷刻即定，非心、肝、肾之痰用熟地之明验乎。（〔批〕心火郁、肝气逆、肾水衰，皆
能生痰，非熟地不能化也。）更有一种，朝夕之间，所吐皆白沫，日轻而夜重，甚则卧不能
倒。用六味汤，大加熟地、山茱萸，一边数服，而痰即大减，再服数十剂，白沫尽消而卧亦
甚安，又非熟地消痰之明验乎。熟地消痰而不生痰，又何疑哉。至于气之滞也，服地黄汤而
消痰于顷刻，犹谓气之不行也可乎。（〔批〕熟地行气而不滞气，论实创开。）人生饮食，脾
肾之气行，水谷入腹，不变痰而变精。惟其脾肾之虚也，水谷入腹，不化精而化痰矣。用地
黄汤而痰消者，往往多能健饭，是熟地乃开胃之圣品也。其所以能开胃者何也？胃为肾之关
，肾水旺而胃中之津液自润，故肾气足而胃气亦足，肾气升而胃气亦升也。然则熟地行气而
非滞气，不又可共信哉。气行痰消，乌能作喘，尤所不必疑者矣。（〔批〕阴虚之人胃气不
开，用熟地反易饥而嗜食，胃中阴邪散而正气伸，故开胃。）
或问熟地既是君药，亦可单用一味以奏功乎？夫熟地虽是君药，不可独用之以取胜。盖
阳药
可以奇用，而阴药必须耦用也。况熟地乃至阴之品，性又至纯，非佐之偏胜之药，断断不能
成功，此四物汤补血所以必益之当归、白芍、川芎也。推之而与人参同用，可以补心肾之既
济；与白术同用，可以补脾肾之有亏；与麦冬、五味同用，可以滋肺肾之将枯；与白芍同用
，可以益肝肾之将绝；与肉桂同用，可以助命门之火衰。与枣仁同用，可以安膻中之火沸；
与地榆同用，可以清大肠之血；与沙参同用，可以凉胃中之炎。与元参同用，可以泻阳明之
焰。然必用至一两、二两为君，而加所佐之味，或五钱或八钱，自易取胜于万全也。倘熟
地
少用，其力不全，又何以取胜哉。内惟肉桂止可用一二钱，不可用至三钱之外，余则可与熟
地多用而无忌者也。
或问产前必用熟地以补血，不识产后亦可重用乎？曰∶产后正宜重用也。产妇血大亏，
不用
熟地以生新血，用何药乎？虽佛手散乃产后圣药，然能加入熟地，则生血尤奇。凡产后血晕
诸病，同人参、当归并用，必建殊功，不特产后脐腹急痛者始可用之也。夫肾中元气，为
后天之祖，熟地禀先天之气而生，产妇亏损血室，元气大耗，后天之血既不能速生，正藉先
天之气以生之。用熟地以助后天，实有妙理，非泛论也。
或问熟地腻膈生痰，世人以姜汁、砂仁制之可乎？顾熟地何尝腻膈也。熟地味甘而性温，
味
甘为脾胃所喜，性温为脾胃所宜，脾胃既不相忤，又何所忌而腻膈哉。况熟地乃阴分之药，
不留胃中，即留肾中。胃为肾之关门，胃见肾经之味，有不引导至肾者乎，腻膈之说，起于
不知医理之人，而不可惑深知医理之士也。虽姜汁开胃，砂仁苏脾，无碍于熟地，而终不可
谓熟地之腻膈生痰耳。（〔批〕自腻膈生痰之说出，世人畏熟地而不敢用，今得远公阐发，
可以破惑矣。）
或谓熟地既不腻膈，何以六味地黄丸中加茯苓、山药、泽泻，非因其腻隔而用之乎？是
以茯
苓、山药、泽泻，为制熟地之品，亦何其轻视茯苓、山药、泽泻哉。肾宜补而不宜泻，既用
熟地以补肾，岂可复用利药以泻肾，况又用利药以制补肾之药，使之有泻而无补乎，是熟地
之不宜制也明矣。熟地既不宜制，用茯苓、山药、泽泻之三味，非因制熟地也，亦明矣。熟
地既不宜制，用茯苓、山药、泽泻之三味，非因熟地之腻膈也，抑
又明矣。然则用三味之意谓何？因熟地但能滋
阴而不能去湿，但能补水而不能生阳，用三味以助其成功，非用三味而掣其手足也。
或问熟地既不腻膈，何以生痰，前人言之，岂无见而云然乎？曰∶熟地实消痰圣药，而
世反
没其功，此余所以坚欲辨之也。凡痰之生也，起于肾气之虚，而痰之成也，因于胃气之弱。
肾气不虚，则胃气亦不弱。肾不虚则痰无从生，胃不弱则痰无由成也。然则欲痰之不成，必
须补胃，而欲痰之不生，必须补肾。肾气足而胃气亦足，肾无痰而胃亦无痰。熟地虽是补肾
之药，实亦补胃之药也。胃中津液原本于肾，补肾以生胃中之津液，是真水升于胃矣。真水
升于胃，则胃中邪水自然难存，积滞化而痰涎消，有不知其然而然之妙。熟地消痰不信然乎
，而可谓其腻膈而生痰乎。
或问熟地补肾中之水，何必又用山药、山萸以相佐。盖肾水非得酸不能生，山茱萸味酸
而性
又温，佐熟地实有水乳之合。然而山茱萸味过于酸，非得熟地之甘温，山茱萸亦不能独生肾
水也。配合相宜，如夫妇之好合，以成既济之功也。
或问熟地入于八味地黄丸中，何独为君？盖八味丸补肾中之火也。然火不可以独补，必
须于
水中补之。补火既须补水，则补水之药必宜为君矣。方中诸药，惟熟地乃补水之圣药，故以
之为君。有君则有臣，而山药、山茱佐之。有臣则有佐使，而丹皮、泽泻、茯苓从之。至于
桂、附，反似宾客之象。盖桂附欲补火而无能自主，不得不推让熟地为君，补水以补火也。
或问熟地可独用以治病乎？熟地亦可以独用者也。凡遇心肾不交之病，只消熟地二两，煎汤
饥服，而心肾交于眉睫。人以为熟地乃肾经之药，谁知其能上通于心乎。夫心肾不交之病，
多是心火太过而肾水大亏也。用熟地以滋其肾中之枯干，肾得水之滋，而肾之津即上济于心
，心得肾之济，而心之气即下交于肾，又何黄连、肉桂之多事哉。
或问熟地既可单用以成功，凡遇心肾不交之病，竟用熟地一味为丸，朝夕吞服之得乎？
此则
又不宜也。熟地单用，只可偶尔出奇，要必须辅之以茯神、山药，佐之以山茱、枣仁，始可
久用以成功耳。
或问熟地宜多用以奏功，抑宜少用以取效乎？熟地宜多不宜少也。然而用之得宜，虽重
用数
两不见多；用之失宜，虽止用数钱未见少。用之于肾水大亏之日，多用犹觉少；用之于脾土
大崩之时，少用亦觉多；用之于肾火沸腾之病，用多而殊欠其多；用之于胃土喘胀之症，用
少而殊憎其少。全在用之得宜，而多与不多，不必计也。
或疑熟地腻滞，补阴过多，终有相碍，未可单用一味以取胜，然前人亦有用一味以成功
者何
也？愚谓熟地单用以出奇，实偶然权宜之法，不若佐之他味，使两味以建功之更胜。如治心
肾之亏也，加入龙眼肉；如肝肾之亏也，加入白芍；如治肺肾之亏也，加入麦冬。如治脾肾
之亏也，加入人参，或加白芍。既无腻膈，更多捷效，是在人之权变耳。（〔批〕又开无数
法门。）
或疑肾虚者，宜用熟地，以阴补阴也，何以补胃者亦用之，补胆者亦用之耶？此固古人
权宜
之法，然亦至当之法也。夫胃为肾之关门，肾虚则胃亦虚，补肾正所以补胃也。胆虽附于肝
，而胆之汁必得肾之液渗入，始无枯涸之忧。肾虚则胆亦虚，补肾正所以补胆也。倘见胃之
虚而徒用补胃之药，则香燥之品，愈烁其肾水之干；见胆之虚而只用补胆之味，则酸涩之
剂，愈耗其肾水之竭。肾水既虚，而胃胆愈弱矣。惟用熟地
以补肾，而胃与胆取给于肾而有余，自然燥者不燥，而枯者不枯，谁谓阳症不宜补阴哉。
或疑熟地至阴之药，多用之以滋肾宜也。然何以至阳之病，古人亦用以奏效，岂熟地亦阳分
药乎？熟地非阳分药也。非阳分之药而偏用之以治阳病者，阳得阴而平也。阳非阴不伏，用
熟地以摄至阳之气，则水升火降，阴阳有既济之美矣。
或疑熟地滋阴而不能开胃，孰知熟地正开胃之神药也。胃为肾之关门，肾中枯槁，全藉
胃之
关门，搬运水谷以济其困乏，岂有肾中所喜之物，而胃反拒绝之理。况肾虚无水，则胃中无
非火气，亦望真阴之水以急救其干涸也。然则熟地正胃之所喜，不独肾之所喜也。安有所喜
者投之，不亟为开关以延入者乎，所以肾虚之人。必用熟地以开胃耳。至于肾水不亏，胃中
无火，一旦遽用熟地，未免少加胀闷，是不善用熟地也。谁谓熟地尽闭胃之物哉。
熟地黄，味道甘甜，性质温和，质地沉降，属于阴中之阳，没有毒性。归入肝、肾两经。能够生成血液、补益精髓，促进骨骼和脑髓的生长。
真阴之气如果没有它就无法滋生，虚火的火焰如果没有它就无法降伏。这确实是挽救生命的珍贵药材，延年益寿的奇妙滋味啊。世人因为觉得它滋腻碍胃，丢弃而不用，这也是不了解它的功效罢了。肾脏只有补法而没有泻法，所以肾脏必定适宜进补。然而补肾的药物，确实苦于不多。除了山茱萸、牛膝、杜仲、北五味子之外，舍弃熟地黄还能用什么药呢？况且山茱萸、牛膝不能作为主药（君药），而杜仲的性质又过于温燥，只能补充肾中阳气的衰弱，而不能补充肾中阴液的匮乏。这就是熟地黄必须被使用的原因。熟地黄作为主药，用量可以从一两用到八两。大概补阴的药物与补阳的药物，用法确实有所不同。补阳的药物，少量使用就能见效；而补阴的药物，必须大量使用才能取效。因为阳气主升发而阴气主沉降。阳气上升，少量使用阳药，气机容易上腾；阴气下降，少量使用阴药，药味难以下达。熟地黄是至阴的药物，尤其与其他阴药不同，不大量使用，怎么能取胜呢？有人说道：熟地黄是至阴的药物，但它的性质非常滞涩，如果大量使用会导致膈部痞闷、产生痰湿，万一助长痰湿引发气喘，也是非常危险的。这正是不知道熟地黄的功力所在。自从神农尝百草之后，这一味药的妙用就被遗失不谈了，致使后世之人不了解其中的奥妙。虽然历代名医多有阐发，但也未曾言说其隐秘精奥之处。难道熟地黄仅仅是不生痰吗？它甚至能消除痰湿；难道仅仅是不滞气吗？它善于行气，关键在于人们如何使用它罢了。痰有来源于五脏的不同。痰出自脾、肺者，使用熟地黄会助长湿气，似乎不宜使用。但如果痰出自心、肝、肾者，舍弃熟地黄又用什么来驱逐它呢？所以有人吐出像清水一样的痰，使用二陈汤等消痰化痰的药物，一百次也没有一次成功，却服用八味丸后，汹涌的痰气顷刻间就平息了，这不是心、肝、肾之痰使用熟地黄的有效证明吗？（批注：心火郁结、肝气逆乱、肾水衰竭，都能生痰，非熟地黄不能化解。）还有一种情况，早晚之间吐出的都是白沫，白天轻晚上重，严重时躺卧不得安宁。使用六味地黄丸，大量加入熟地黄、山茱萸，连续服用几次，痰量就大大减少，再服用几十剂，白沫完全消失，睡眠也非常安稳，这又不是熟地黄消除痰湿的有力证明吗？熟地黄消除痰湿而不产生痰湿，又有什么可怀疑的呢？至于气机阻滞的问题，服用地黄汤在顷刻间消除了痰湿，还说气机不能运行，可以吗？（批注：熟地黄行气而不滞气，这种论断实在开创了先河。）人生饮食，依靠脾肾之气的运行，水谷进入腹部，如果不变成痰就会变成精微物质。正是因为脾肾虚弱，水谷进入腹部，不化生精微反而化生了痰湿。使用地黄汤后痰湿消除的人，往往大多胃口变好，这说明熟地黄是开胃的圣品。它之所以能开胃，为什么呢？胃是肾脏的门户，肾水旺盛，胃中的津液自然滋润，所以肾气充足，胃气也充足；肾气上升，胃气也随之上升。那么熟地黄行气而不是滞气，不是又可以共同相信了吗？气机运行，痰湿消除，怎么会产生气喘呢？这是特别不必怀疑的了。（批注：阴虚的人胃气不开，使用熟地黄反而容易饥饿且嗜食，因为胃中的阴邪散去而正气伸展，所以能开胃。）
有人问：熟地黄既然是主药，也可以单用一味药来奏效吗？答道：熟地黄虽然是主药，不可以单独使用来取胜。大概阳药可以奇数配伍使用，而阴药必须偶数配伍使用。况且熟地黄是至阴的物品，性质又极其纯正，如果不佐以偏胜的药物，绝对不能成功，这就是四物汤补血时必然要加入当归、白芍、川芎的原因。推而广之，与人参同用，可以补益心肾相交；与白术同用，可以补益脾肾亏损；与麦冬、五味子同用，可以滋润将枯竭的肺肾；与白芍同用，可以增益将绝的肝肾；与肉桂同用，可以助命门之火衰弱的恢复；与酸枣仁同用，可以安顿膻中火热沸腾的状态；与地榆同用，可以清大肠的血热；与沙参同用，可以凉胃中的炎症；与玄参同用，可以泻阳明经的火焰。但是必须用一两、二两作为主药，再加入所佐使的药物，或者五钱或者八钱，自然容易取得万全的效果。如果熟地黄用量少，力量就不全面，又凭什么取胜呢？其中只有肉桂只可用一二钱，不可超过三钱，其余药物都可以与熟地黄多用而无禁忌。
有人问：产前必用熟地黄来补血，不知产后也可以重用吗？答道：产后正宜重用。产妇血液大亏，不用熟地黄来生成新血，还用什么呢？虽然佛手散是产后的圣药，但是如果加入熟地黄，生血的效果更加神奇。凡是产后血晕等疾病，同人参、当归并用，必定建立殊功，不仅仅是产后脐腹急痛的人才可以使用。肾中的元气，是后天的根本，熟地黄禀受先天之气而生，产妇亏损血室，元气大耗，后天的血既然不能快速生成，正借助先天的气来生成它。使用熟地黄来辅助后天，实在有妙理，不是泛泛之论。
有人问：世人认为熟地黄滋腻碍胃生痰，用姜汁、砂仁炮制它可以吗？答道：顾念熟地黄何曾滋腻碍胃呢？熟地黄味道甘甜而性质温和，味甘为脾胃所喜欢，性温为脾胃所适宜，脾胃既然不相抵触，又有什么忌讳而滋腻碍胃呢？况且熟地黄是阴分的药物，不留存在胃中，就留存在肾中。胃是肾的关门，胃见到肾经的味道，没有不引导至肾脏的。滋腻碍胃的说法，起于不懂医理的人，而不可迷惑深知医理的士人。虽然姜汁能开胃，砂仁能醒脾，无碍于熟地黄，但最终不能说熟地黄滋腻碍胃生痰。（批注：自滋腻碍胃生痰之说出现以来，世人畏惧熟地黄而不敢使用，现在得到远公的阐发，可以破除疑惑了。）
有人说：熟地黄既然不滋腻碍胃，为什么六味地黄丸中加入茯苓、山药、泽泻，不是因为它的滋腻碍胃才用的吗？如果把茯苓、山药、泽泻看作是制约熟地黄的药品，这也太轻视茯苓、山药、泽泻了吧。肾脏适宜补而不适宜泻，既然用熟地黄来补肾，岂可再用利水渗湿的药来泻肾？况且又用利水渗湿的药来制约补肾的药，使得它有泻而无补吗？这就明确表明熟地黄不适宜被制约。熟地黄既然不适宜被制约，使用茯苓、山药、泽泻这三味药，不是为了制约熟地黄，也很明白了。熟地黄既然不适宜被制约，使用茯苓、山药、泽泻这三味药，不是因为熟地黄滋腻碍胃，更是显而易见了。那么使用这三味药的意思是什么呢？是因为熟地黄只能滋阴而不能祛湿，只能补水而不能生阳，使用这三味药来辅助它取得成功，不是用这三味药来牵制它的手脚。
有人问：熟地黄既然不滋腻碍胃，为什么还会生痰？前人这么说，难道没有见地吗？答道：熟地黄实在是消除痰湿的圣药，而世人反而埋没了它的功效，这就是我坚决想要辩驳的原因。凡痰的产生，起于肾气虚弱，而痰的形成，在于胃气微弱。肾气不虚，则胃气也不弱。肾不虚则痰无从产生，胃不弱则痰无由形成。那么想要痰不形成，必须补胃；想要痰不产生，必须补肾。肾气足而胃气也足，肾无痰而胃也无痰。熟地黄虽然是补肾的药，实际上也是补胃的药。胃中的津液原本源于肾，补肾以生成胃中的津液，这是真水升于胃了。真水升于胃，则胃中的邪水自然难以存留，积滞化解而痰涎消除，有不知不觉的奇妙之处。熟地黄消除痰湿，不确实是这样吗？怎么能说它滋腻碍胃而生痰呢？
有人问：熟地黄补肾中的水，何必又用山药、山茱萸来辅助？答道：肾水如果不是酸味的药物就不能生成，山茱萸味道酸而性质又温，辅助熟地黄实在有水乳交融的结合。然而山茱萸味道过于酸，如果不是熟地黄的甘温，山茱萸也不能独自生成肾水。配合相宜，如同夫妇的好合，以达成水火既济的功效。
有人问：熟地黄进入八味地黄丸中，为什么唯独它是主药？答道：大概八味丸是补肾中的火。然而火不可以单独补，必须从水中补。补火既然需要补水，那么补水的药物就应当作为主药。方中的各种药物，只有熟地黄是补水的圣药，所以把它作为主药。有主药就有臣药，而山药、山茱萸辅助它。有臣药就有佐使药，而牡丹皮、泽泻、茯苓跟随它。至于肉桂、附子，反而像是宾客的样子。大概肉桂、附子想补火却没有能力自主，不得不推让熟地黄作为主药，通过补水来补火。
有人问：熟地黄可以单独使用来治病吗？答道：熟地黄也可以单独使用。凡是遇到心肾不交的疾病，只要用熟地黄二两，煎汤在饥饿时服用，心肾就在眉睫之间相交。人们以为熟地黄是肾经的药物，谁知道它能上通于心呢？心肾不交的疾病，多是心火太过而肾水大亏。使用熟地黄来滋润肾中的枯干，肾得到水的滋润，肾的津液就上济于心；心得到肾的济助，心的气就下交于肾，哪里还需要黄连、肉桂多此一举呢？
有人问：熟地黄既然可以单用取得成功，凡是遇到心肾不交的疾病，竟然只用熟地黄一味药做成丸剂，早晚吞服，可以吗？答道：这又不适宜了。熟地黄单用，只可偶尔出奇，必须要辅佐茯神、山药，佐使山茱萸、酸枣仁，才可以长久使用来取得成功。
有人问：熟地黄适宜多用还是少用以取效？答道：熟地黄宜多不宜少。然而使用得当，即使重用几两也不觉得多；使用不当，即使只用几钱也不觉得少。用在肾水大亏的时候，多用还觉得少；用在脾土大崩的时候，少用也觉得多；用在肾火沸腾的病证，用多了还觉得不够；用在胃土喘胀的症状，用少了还觉得嫌少。全在于使用得当，多与不多，不必计较。
有人怀疑熟地黄滋腻滞涩，补阴过多，终究会有妨碍，不可单用一味药来取胜，然而前人也有用一味药成功的，为什么呢？我认为熟地黄单用来出奇，实在是偶然的权宜之法，不如佐以其他药物，使两味药建功更胜。比如治疗心肾亏损，加入龙眼肉；比如肝肾亏损，加入白芍；比如治疗肺肾亏损，加入麦冬。比如治疗脾肾亏损，加入人参，或加白芍。既没有滋腻碍胃，又有更快的疗效，这在于人的权变罢了。（批注：又开启了无数法门。）
有人怀疑肾虚者，宜用熟地黄，是以阴补阴，为什么补胃也用它，补胆也用它呢？这固然是古人的权宜之法，但也是极恰当的方法。胃是肾脏的门户，肾虚则胃也虚，补肾正是为了补胃。胆虽然依附于肝，但胆的汁液必须得到肾的液体渗入，才没有枯涸的忧虑。肾虚则胆也虚，补肾正是为了补胆。如果见到胃虚而徒然使用补胃的药物，那么香燥的药物，会更加灼烧肾水的干枯；见到胆虚而只用补胆的药物，那么酸涩的药剂，会更加耗竭肾水。肾水既然虚弱，而胃和胆更加衰弱了。只有用熟地黄来补肾，而胃和胆从肾中获取供给而有余，自然干燥的不干燥，枯涸的不枯涸，谁说阳症不适宜补阴呢？
有人怀疑熟地黄是至阴的药物，多用它以滋肾是适宜的。然而为什么对于至阳的病，古人也用它奏效，难道熟地黄也是阳分药吗？答道：熟地黄不是阳分药。不是阳分的药物却偏用它来治阳病，是因为阳得到阴的制约而平和。阳没有阴就不能潜伏，使用熟地黄来摄纳至阳之气，则水升火降，阴阳有了既济的美好状态。
有人怀疑熟地黄滋阴而不能开胃，孰知熟地黄正是开胃的神药。胃是肾脏的门户，肾中枯槁，全赖胃的门户，搬运水谷来救济它的困乏，哪里有肾中所喜欢的东西，而胃反而拒绝的道理？况且肾虚无水，则胃中无非是火气，也盼望真阴之水来急救它的干涸。那么熟地黄正是胃所喜欢的，不只是肾所喜欢的。有什么喜欢的投喂它，没有急于打开门户迎接它进入的吗？所以肾虚的人，必须用熟地黄来开胃。至于肾水不亏，胃中没有火，一旦突然使用熟地黄，未免稍微有些胀闷，这是不善于使用熟地黄。谁说熟地黄是闭塞胃口的东西呢？
Shu Di Huang (Prepared Rehmanniae Radix), with a sweet taste and warm nature, is heavy and sinking. It belongs to the category of "Yang within Yin" and is non-toxic. It enters the Liver and Kidney meridians. It generates blood, nourishes essence, and promotes the growth of marrow in the bones and brain.
The Qi of True Yin cannot be generated without it, and the flames of Deficient Fire cannot be subdued without it. Indeed, it is a miraculous substance that saves lives and a wonderful flavor that prolongs longevity. People discard it because they consider it cloying and obstructive, failing to understand its efficacy. The Kidney is only suited for tonification and not for purgation; thus, the Kidney must certainly be tonified. However, there are few herbs suitable for tonifying the Kidney. Besides Cornus Officinalis Fructus (Shanzhuyu, 山茱萸), Achyranthes Bidentatae Radix (Niuxi, 牛膝), Eucommia Ulmoides Cortex (Duzhong, 杜仲), and Schisandra Chinensis Fructus (Beiwuweizi, 北五味子), what other herb can be used besides Shu Di Huang? Moreover, Cornus Officinalis Fructus and Achyranthes Bidentatae Radix cannot serve as the Sovereign herb (Jun Yao, 君药), while Eucommia Ulmoides Cortex is too warm in nature; it can tonify the decline of Kidney Yang but cannot replenish the deficiency of Kidney Yin. This is why Shu Di Huang must be used. As a Sovereign herb, Shu Di Huang can be used from one liang up to eight liang. Generally, the usage of Yin-tonifying herbs differs significantly from Yang-tonifying herbs. Yang-tonifying herbs can achieve results with small doses, whereas Yin-tonifying herbs require large doses to be effective. This is because Yang governs ascending and Yin governs descending. When Yang ascends, a small dose of Yang herb allows Qi to rise easily; when Yin descends, a small dose of Yin herb makes it difficult for the medicinal flavor to reach the lower body. Shu Di Huang is an herb of extreme Yin, distinct from other Yin herbs; without using it in large quantities, how can it succeed? Some argue: Shu Di Huang is an herb of extreme Yin, and its nature is very stagnant. Using it in large quantities may cause chest oppression and generate phlegm; if it exacerbates phlegm leading to asthma, it would be very dangerous. This shows a lack of understanding of Shu Di Huang's power. Since Shennong tasted the herbs, the discussion of this herb was lost, causing later generations to be unaware of its secrets. Although many famous doctors of past dynasties have elucidated its properties, they have rarely revealed its profound mysteries. Does Shu Di Huang merely avoid generating phlegm? It can actually eliminate phlegm. Does it merely avoid stagnating Qi? It excels at promoting Qi movement. It depends on how people use it. Phlegm originates differently from the five Zang organs. If phlegm comes from the Spleen or Lung, using Shu Di Huang may aggravate dampness, making it seemingly unsuitable. However, if phlegm originates from the Heart, Liver, or Kidney, what else can be used to expel it besides Shu Di Huang? For instance, some patients expectorate phlegm like clear water. Treatments with Er Chen Tang (Two-Cured Decoction) and other phlegm-resolving drugs fail hundred times out of a hundred. Yet, after taking Ba Wei Wan (Eight-Ingredient Pill), the surging phlegm subsides instantly. Is this not clear evidence that Shu Di Huang treats phlegm from the Heart, Liver, and Kidney? [Commentary: Heart Fire stagnation, Liver Qi rebellion, and Kidney Water depletion can all generate phlegm, which only Shu Di Huang can resolve.] Another type involves expectorating white foam day and night, lighter in the morning and heavier at night, severe enough to prevent lying down. Using Liu Wei Wan (Six-Ingredient Pill) with a large addition of Shu Di Huang and Cornus Officinalis Fructus, after several doses, the phlegm decreases significantly. After dozens more doses, the white foam disappears completely, and sleep becomes peaceful. Is this not further proof of Shu Di Huang's ability to resolve phlegm? There is no doubt that Shu Di Huang resolves phlegm without generating it. Regarding Qi stagnation, if Dihuang Tang (Rehmannia Decoction) resolves phlegm instantly, how can one claim that Qi does not move? [Commentary: Shu Di Huang moves Qi without stagnating it; this argument truly breaks new ground.] In human digestion, the Qi of the Spleen and Kidney facilitates the transformation of food and water. If the Spleen and Kidney are strong, food transforms into Essence rather than Phlegm. Due to Spleen and Kidney deficiency, food transforms into Phlegm instead of Essence. Patients whose phlegm is resolved by Dihuang Tang often regain their appetite, proving that Shu Di Huang is a sacred item for opening the stomach. Why can it open the stomach? The Stomach is the gate of the Kidney. When Kidney Water is abundant, Stomach fluids are naturally moistened. Thus, sufficient Kidney Qi leads to sufficient Stomach Qi; rising Kidney Qi leads to rising Stomach Qi. Therefore, Shu Di Huang moves Qi rather than stagnating it, which should be universally accepted. With moving Qi and resolving phlegm, how could asthma arise? This needs no doubt. [Commentary: In individuals with Yin deficiency, Stomach Qi is closed; using Shu Di Huang反而 increases hunger and desire for food, as Stomach Yin pathogens dissipate and Righteous Qi extends, thus opening the stomach.]
Someone asks: Since Shu Di Huang is a Sovereign herb, can it be used alone to achieve efficacy? Answer: Although Shu Di Huang is a Sovereign herb, it should not be used alone to succeed. Yang herbs can be used in odd-numbered combinations, but Yin herbs must be used in even-numbered combinations. Moreover, Shu Si Huang is an extreme Yin substance with pure nature. Without assisting it with herbs of biased nature, success is impossible. This is why Si Wu Tang (Four-Substance Decoction) must include Angelica Sinensis Radix (Danggui, 当归), Paeonia Lactiflora Radix Alba (Baishao, 白芍), and Chuanxiong Rhizoma (Chuanxiong, 川芎) to tonify blood. Extending this principle: combined with Ginseng Radix et Rhizoma (Renshen, 人参), it tonifies the mutual interaction of Heart and Kidney; combined with Atractylodis Macrocephalae Rhizoma (Baizhu, 白术), it tonifies Spleen and Kidney deficiencies; combined with Ophiopogon Japonicus Radix (Maidong, 麦冬) and Schisandra Chinensis Fructus (Wuweizi, 五味子), it nourishes the drying Lung and Kidney; combined with Paeonia Lactiflora Radix Alba (Baishao, 白芍), it benefits the nearly exhausted Liver and Kidney; combined with Cinnamomi Cortex (Rougui, 肉桂), it assists the declining Fire of the Gate of Vitality (Mingmen, 命门); combined with Ziziphus Jujube Seed (Suanzaoren, 酸枣仁), it calms the boiling Fire in the Epigastrium (Shanzhong, 膻中); combined with Sanguisorbae Radix (Diyu, 地榆), it clears Blood heat in the Large Intestine; combined with Glehniae Radix (Shashen, 沙参), it cools inflammation in the Stomach; combined with Scrophulariae Radix (Xuanshen, 玄参), it drains the flames of the Yangming channel. However, Shu Di Huang must be used as the Sovereign herb in amounts of one to two liang, with assisting herbs added in amounts of five or eight qian, ensuring complete success. If Shu Di Huang is used in small amounts, its power is incomplete, and it cannot succeed. Only Cinnamomi Cortex (Rougui, 肉桂) should be limited to one or two qian, not exceeding three qian; other herbs can be used in larger quantities alongside Shu Di Huang without禁忌.
Someone asks: Shu Di Huang is essential for tonifying blood before childbirth; can it also be heavily used after childbirth? Answer: Heavy use is precisely indicated after childbirth. Postpartum women suffer from severe blood loss. What herb can generate new blood if not Shu Di Huang? Although Fo Shou San (Buddha's Hand Powder) is a sacred postpartum remedy, adding Shu Di Huang makes its blood-generating effect even more miraculous. For various postpartum conditions like syncope due to blood loss, combining it with Ginseng Radix et Rhizoma (Renshen, 人参) and Angelica Sinensis Radix (Danggui, 当归) yields remarkable results, not just for those with urgent abdominal pain. The Original Qi in the Kidney is the ancestor of Postnatal Qi. Shu Di Huang is born bearing Pre-natal Qi. Postpartum women deplete the Blood Chamber and exhaust Original Qi. Since Postnatal blood cannot be quickly regenerated, it relies on Pre-natal Qi to generate it. Using Shu Di Huang to assist the Postnatal aspect contains profound principles, not mere generalizations.
Someone asks: People believe Shu Di Huang is cloying and generates phlegm; is it acceptable to process it with Ginger Juice (Jiangzhi, 姜汁) and Amomum Fruit (Sharen, 砂仁)? Answer: Consider whether Shu Di Huang is ever cloying. Shu Di Huang is sweet and warm. Sweetness is favored by the Spleen and Stomach; warmth is suitable for them. Since the Spleen and Stomach do not conflict with it, why would it cause cloying obstruction? Furthermore, Shu Di Huang is an herb of the Yin aspect. It either stays in the Stomach or moves to the Kidney. The Stomach is the gate of the Kidney. When the Stomach encounters the flavor of the Kidney meridian, it guides it to the Kidney. The idea of cloying obstruction arises from those who do not understand medical principles and should not confuse experts. Although Ginger Juice opens the stomach and Amomum Fruit awakens the Spleen, neither hinders Shu Di Huang, yet one cannot say Shu Di Huang causes cloying obstruction and generates phlegm. [Commentary: Since the emergence of the theory that it causes cloying obstruction and generates phlegm, people feared Shu Di Huang and dared not use it. Now, with Far Gong's elucidation, confusion can be dispelled.]
Some say: If Shu Di Huang is not cloying, why are Poria (Fuling, 茯苓), Dioscorea Hypoglauca Rhizome (Shanyao, 山药), and Alisma Orientale Rhizome (Zexie, 泽泻) added to Liu Wei Di Huang Wan (Six-Ingredient Rehmannia Pill)? Isn't it because of its cloying nature? To view Poria, Dioscorea Hypoglauca Rhizome, and Alisma Orientale Rhizome merely as agents to restrain Shu Di Huang is to underestimate them greatly. The Kidney is suited for tonification, not purgation. If we use Shu Di Huang to tonify the Kidney, how can we use diuretics to purge the Kidney? And using diuretics to restrain a Kidney-tonifying herb creates purgation without tonification. It is clear that Shu Di Huang should not be restrained. Consequently, the use of Poria, Dioscorea Hypoglauca Rhizome, and Alisma Orientale Rhizome is not to restrain Shu Di Huang, nor is it due to Shu Di Huang's cloying nature. Then, what is the purpose of these three herbs? Shu Di Huang can nourish Yin but not remove dampness; it can tonify Water but not generate Yang. These three herbs are used to assist its success, not to hinder it.
Someone asks: If Shu Di Huang is not cloying, why does it generate phlegm? Did previous authors speak without basis? Answer: Shu Di Huang is truly a sacred herb for resolving phlegm, yet the world obscures its merit, which is why I insist on refuting this. Phlegm generation starts with Kidney Qi deficiency, and phlegm formation depends on weak Stomach Qi. If Kidney Qi is not deficient, Stomach Qi is not weak. If the Kidney is not deficient, phlegm has no source; if the Stomach is not weak, phlegm has no means of formation. To prevent phlegm formation, one must tonify the Stomach; to prevent phlegm generation, one must tonify the Kidney. When Kidney Qi is sufficient, Stomach Qi is sufficient; the Kidney has no phlegm, so the Stomach has no phlegm. Shu Di Huang, though a Kidney-tonifying herb, is also a Stomach-tonifying herb. Stomach fluids originate from the Kidney. Tonifying the Kidney generates Stomach fluids, allowing True Water to ascend to the Stomach. When True Water ascends, Evil Water in the Stomach cannot survive. Accumulations transform, and saliva/phlegm dissolves, achieving a subtle effect unknowingly. Is it not true that Shu Di Huang resolves phlegm? How can it be said to cause cloying obstruction and generate phlegm?
Someone asks: Shu Di Huang tonifies Kidney Water; why add Dioscorea Hypoglauca Rhizome (Shanyao, 山药) and Cornus Officinalis Fructus (Shanzhuyu, 山茱萸)? Answer: Kidney Water cannot be generated without sour flavors. Cornus Officinalis Fructus is sour and warm, complementing Shu Di Huang like milk and water. However, its sourness is excessive; without the sweet-warm nature of Shu Di Huang, it cannot independently generate Kidney Water. Their combination is harmonious, like a marital union, achieving the state of Mutual Interaction (Ji Ji, 既济).
Someone asks: In Ba Wei Di Huang Wan (Eight-Ingredient Rehmannia Pill), why is Shu Di Huang the Sovereign herb? Answer: Ba Wei Di Huang Wan tonifies Kidney Fire. However, Fire cannot be tonified alone; it must be tonified within Water. Since tonifying Fire requires tonifying Water, the water-tonifying herb must be the Sovereign. Among the formula's ingredients, only Shu Di Huang is the sacred herb for tonifying Water, hence it serves as the Sovereign. With a Sovereign, there are Ministers; Dioscorea Hypoglauca Rhizome and Cornus Officinalis Fructus assist it. With Ministers, there are Guides and Messengers; Paeonia Moutan Cortex (Danpi, 丹皮), Alisma Orientale Rhizome (Zexie, 泽泻), and Poria (Fuling, 茯苓) follow. Cinnamon Twig (Guizhi, 桂枝) and Aconite Root (Fuzi, 附子) resemble guests. They wish to tonify Fire but lack autonomy, yielding precedence to Shu Di Huang to tonify Fire via tonifying Water.
Someone asks: Can Shu Di Huang be used alone to treat disease? Answer: Yes. For diseases of Heart-Kidney Non-Interaction, using two liang of Shu Di Huang, decocted and taken on an empty stomach, brings the Heart and Kidney into immediate interaction. People think Shu Di Huang only enters the Kidney meridian, not knowing it connects upward to the Heart. Heart-Kidney Non-Interaction usually involves excessive Heart Fire and severe Kidney Water deficiency. Shu Di Huang nourishes the dryness in the Kidney. Nourished by Water, Kidney fluids ascend to benefit the Heart. Benefited by the Kidney, Heart Qi descends to interact with the Kidney. What need is there for Coptis Rhizome (Huanglian, 黄连) and Cinnamon Twig (Guizhi, 桂枝)?
Someone asks: If Shu Di Huang can succeed alone, can one make pills of single-shard Shu Di Huang for Heart-Kidney Non-Interaction and take them morning and night? Answer: This is inappropriate. Single-use of Shu Di Huang is for occasional surprise effects. For long-term success, it must be assisted by Polyporus (Fushen, 茯神) and Dioscorea Hypoglauca Rhizome (Shanyao, 山药), and guided by Cornus Officinalis Fructus (Shanzhuyu, 山茱萸) and Ziziphus Jujube Seed (Suanzaoren, 酸枣仁).
Someone asks: Should Shu Di Huang be used in large or small doses? Answer: It should be used in large doses, not small. However, proper usage matters. Even heavy doses of several liang are not too much if used correctly; even small doses of several qian are too much if used incorrectly. Used during severe Kidney Water deficiency, even large doses feel insufficient. Used during massive Spleen Earth collapse, even small doses feel excessive. Used for boiling Kidney Fire, even large doses feel lacking. Used for Stomach Earth wheezing and distension, even small doses feel disliked. Success depends entirely on proper usage; quantity is secondary.
Someone doubts: Shu Di Huang is cloying and stagnating; excessive Yin tonification may hinder function, so it shouldn't be used alone. Yet predecessors succeeded with single herbs. Why? Answer: Single-use of Shu Di Huang is a temporary expedient for surprising results. It is superior to combine it with other herbs for better efficacy. For Heart-Kidney deficiency, add Longan Aril (Longyanrou, 龙眼肉); for Liver-Kidney deficiency, add Paeonia Lactiflora Radix Alba (Baishao, 白芍); for Lung-Kidney deficiency, add Ophiopogon Japonicus Radix (Maidong, 麦冬); for Spleen-Kidney deficiency, add Ginseng Radix et Rhizoma (Renshen, 人参) or Paeonia Lactiflora Radix Alba (Baishao, 白芍). This avoids cloying obstruction and yields faster results, depending on clinical flexibility. [Commentary: This opens countless methods.]
Someone doubts: Kidney deficiency suits Shu Di Huang (tonifying Yin with Yin), but why is it also used for Stomach and Gallbladder deficiency? Answer: This is an ancient expedient but also a highly appropriate method. The Stomach is the gate of the Kidney. Kidney deficiency leads to Stomach deficiency; tonifying the Kidney is indeed tonifying the Stomach. The Gallbladder attaches to the Liver, but its juice requires Kidney fluid infiltration to avoid drying up. Kidney deficiency leads to Gallbladder deficiency; tonifying the Kidney is indeed tonifying the Gallbladder. If one sees Stomach deficiency and uses only Stomach-tonifying herbs, aromatic-dry substances will further scorch Kidney Water. If one sees Gallbladder deficiency and uses only Gallbladder-tonifying herbs, sour-astringent agents will further deplete Kidney Water. With depleted Kidney Water, the Stomach and Gallbladder become weaker. Only by tonifying the Kidney with Shu Di Huang can the Stomach and Gallbladder draw sufficient support, remaining moist and hydrated. Who says Yang syndromes should not be treated with Yin tonification?
Someone doubts: Shu Di Huang is an extreme Yin herb; using it heavily to nourish the Kidney is appropriate. But why did ancients use it effectively for extreme Yang diseases? Is Shu Di Huang a Yang herb? Answer: Shu Di Huang is not a Yang herb. Using a non-Yang herb for Yang diseases works because Yang is balanced by Yin. Yang cannot settle without Yin. Using Shu Di Huang to capture extreme Yang Qi allows Water to ascend and Fire to descend, achieving the beauty of Mutual Interaction (Ji Ji, 既济).
Someone doubts: Shu Di Huang nourishes Yin but doesn't open the stomach. Who knew it was a sacred herb for opening the stomach? The Stomach is the gate of the Kidney. When the Kidney is withered, it relies on the Stomach gate to transport food and water to relieve distress. Would the Stomach reject what the Kidney desires? Moreover, with Kidney deficiency and lack of Water, the Stomach is filled with Fire, longing for True Yin Water to save it from drought. Thus, Shu Di Huang is pleasing to both the Stomach and the Kidney. Why would the Stomach not eagerly open its gates to welcome it? Therefore, Kidney-deficient patients must use Shu Di Huang to open the stomach. If Kidney Water is not deficient and there is no Fire in the Stomach, sudden use of Shu Di Huang may cause slight bloating; this is improper usage. Who says Shu Di Huang closes the stomach?