薏苡仁，味甘，气微寒，无毒。入脾、肾二经，兼入肺。疗湿痹有神，舒筋骨拘挛，止
骨中
疼痛，消肿胀，利小便，开胃气，亦治肺痈。但必须用至一、二两，始易有功，少亦须用五
钱之外，否则，力薄味单耳。薏仁最善利水，又不损耗真阴之气。凡湿感在下体者，最宜用
之。视病之轻重，准用药之多寡，则阴阳不伤，而湿病易去。人见用药之多，动生物议，原
未知药性，无怪其然。余今特为阐明，原世人勿再疑也。凡利水之药，俱宜多用，但多用利
水之药，必损真阴之气，水未利，而阴且虚矣，所以他利水之药，不敢多用。惟薏仁利水，
而又不损真阴之气，诸利水药所不及者也。可以多用，而反不用，与不可多用，而反大用者
，
安得有利乎。故凡遇水湿之症，用薏仁一、二两为君，而佐之健脾去湿之味，未有不速于奏
效者也。倘薄其气味之平和而轻用之，无益也。（〔批〕薏仁利水而不走气，与茯苓同功。）
或问薏仁味薄而气轻，何以利水之功犹胜？盖薏仁感土气而生，故利气又不损阴。所以
可多
用以出奇，而不必节用以畏缩也。
或问薏仁有取之酿酒者，亦可藉为利湿之需乎？夫薏仁性善利湿，似乎所酿之酒，亦可
以利
湿也。然用薏酒以治湿，而湿不能去，非特湿不能去，而湿且更重，其故何哉？酒性大热，
薏仁既化为酒，则薏仁之气味亦化为热矣，既化为热，独不可化为湿乎，湿热以治湿热，又
何宜哉。此薏仁之酒，断不可取之，以治湿热之病也。
或问薏仁可以消瘴气，而未言及，岂忘之耶？非忘也。薏仁只能消湿气之瘴，而不能消
岚气
之瘴。虽岚气即湿气之类，然而湿气从下受，而岚气从上感，又各不同。薏仁消下部之湿，
安能消上部之湿哉。（〔批〕薏仁消下湿，而不消上湿，确论不磨。）
或问薏仁得地之燥气，兼禀乎天之秋气，似与治痿相宜，何子忘之也？亦未曾忘也。经
曰∶
治痿独取阳明。阳明者，胃与大肠也。二经湿热则成痿，湿去则热亦随解。故治痿者，必去
湿也。吾前言用薏仁至一、二两者，正言治痿病也。天下惟痿病最难治，非多用薏仁，则水
不易消，水不消，则热不能解，故治痿病断须多用耳。推之而凡有诸湿之症，无不宜多用。
正不可因铎之未言，即疑而不用也。
或问薏仁功用甚薄，何不用猪苓、泽泻，可以少用见功，而必多用薏仁，何为乎？不知
利水
之药，必多耗气，薏仁妙在利水而又不耗真气，故可重用之耳。
Coix Seed (Yiyiren), with a sweet taste and slightly cold nature, is non-toxic. It enters the Spleen and Kidney meridians, and also the Lung meridian. It is effective in treating Bi syndrome due to dampness (joint pain and heaviness caused by damp pathogen obstruction), relaxing tendon and bone spasms, relieving bone pain, reducing swelling, promoting urination, opening the stomach qi, and treating lung abscess (purulent lesions in the lungs). However, a dosage of one to two taels is required for efficacy; even the minimum dose should be five qian, otherwise the medicinal power is weak and the flavor too simple. Coix seed excels at promoting water metabolism without depleting True Yin Qi. It is most suitable for cases where dampness affects the lower body. By adjusting the dosage according to the severity of the illness, Yin and Yang remain undamaged, and damp diseases are easily resolved. People often criticize high dosages because they do not understand the properties of herbs, which is understandable. I hereby clarify this point so that people will no longer doubt it. Generally, diuretic herbs are suitable for high doses, but using large amounts of other diuretics inevitably damages True Yin Qi; before the water is eliminated, Yin becomes deficient. Therefore, other diuretics cannot be used in large quantities. Only Coix seed promotes water metabolism without damaging True Yin Qi, surpassing other diuretic herbs. If one can use more but does not, compared to those who use excessively when they should not, how can there be any benefit? Thus, for any water-dampness condition, using one to two taels of Coix seed as the sovereign herb, assisted by herbs that strengthen the Spleen and eliminate dampness, will invariably produce rapid effects. If its mild nature leads to underdosing, it will be of no benefit. (Comment: Coix seed promotes water metabolism without dispersing Zheng Qi, functioning similarly to Poria.)
A question arises: Since Coix seed has a light taste and mild aroma, why is its diuretic effect superior? This is likely because Coix seed grows by absorbing Earth Qi, thus benefiting Qi without damaging Yin. Therefore, it can be used in larger amounts for unexpected results, without the need for restraint or hesitation.
Another question: Can Coix seed wine be used for eliminating dampness? Although Coix seed is good at resolving dampness, the wine made from it may not necessarily resolve dampness effectively. Using Coix seed wine to treat dampness fails to remove the dampness and may even exacerbate it. Why? Wine has a hot nature. Once Coix seed is fermented into wine, its nature transforms into heat. Heat can transform into dampness. Using heat-dampness to treat heat-dampness is inappropriate. Therefore, Coix seed wine must not be used to treat heat-dampness conditions.
Another question: Coix seed can dissipate miasma, yet this was not mentioned. Was it forgotten? No. Coix seed can only dissipate miasma caused by dampness, not miasma caused by mountain mist (Lan Qi). Although mountain mist is a type of dampness, dampness typically enters from below, while mountain mist is contracted from above; they differ significantly. Coix seed eliminates dampness in the lower part of the body; how can it eliminate dampness in the upper part? (Comment: Coix seed eliminates lower dampness but not upper dampness; this is an irrefutable argument.)
Another question: Coix seed absorbs dry Qi from the earth and Autumn Qi from heaven, seemingly suitable for treating Wei syndrome (limb flaccidity). Why did you omit it? It was not omitted. The Classics state: "In treating Wei syndrome, focus solely on the Yangming." Yangming refers to the Stomach and Large Intestine meridians. Damp-heat in these two meridians causes Wei syndrome; removing dampness resolves the heat. Therefore, treating Wei syndrome requires removing dampness. When I previously mentioned using one to two taels of Coix seed, I was referring specifically to treating Wei syndrome. Wei syndrome is the most difficult to treat worldwide. Without using large amounts of Coix seed, water retention is hard to resolve; if water is not resolved, heat cannot be cleared. Thus, large doses are essential for Wei syndrome. By extension, large doses are appropriate for all damp-related conditions. Do not hesitate to use it simply because I did not explicitly emphasize it earlier.
Another question: Coix seed's efficacy seems mild. Why not use Polyporus (Zhuling) or Alisma (Zexie), which show effects at lower doses, instead of heavily relying on Coix seed? One must realize that diuretic herbs tend to consume Qi. The brilliance of Coix seed lies in promoting water metabolism without consuming True Qi, which allows for heavy usage.