Geng Mi (Rice)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Geng Mi, and how is it added to a decoction?

  Roughly 9–30 g, and the amounts recorded in the formulas on this site sit squarely in that range — 9–15 g in Bai Hu Tang, Zhu Ye Shi Gao Tang and Mai Men Dong Tang, 12–15 g in Qing Shu Yi Qi Tang, 15–30 g in Xie Bai San, and 30 g in Tao Hua Tang. As a food, quantity is not rigid; these are formula proportions rather than a dose in the pharmacological sense.

  • The classical cooking instruction — in Bai Hu Tang the rice is added to the decoction and the whole is simmered until the rice is cooked, at which point the decoction is considered finished and the dregs are strained off. The rice is a timer as much as an ingredient: it tells the preparer when the decoction is done.
  • What it contributes physically — cooked rice releases starch, which thickens the liquid and gives the decoction body. Traditional explanation and practical effect line up here: a thicker, starchier liquid sits more gently on the stomach than a thin, bitter, mineral-heavy one.
  • Substitution — where rice is unavailable or a granule preparation is used, the rice component is often omitted or replaced with Shan Yao (Chinese yam), which shares the sweet, Spleen-supporting, fluid-generating character. This is a modern practical convention rather than a classical instruction.

  Source: Sacred Lotus sources & references (recorded formula amounts for all seven formulas listed above); cooking instruction and substitution conventions per materia medica consensus, cross-referenced against multiple online sources. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Geng Mi (rice)?

  None are recorded, and none would be expected: this is plain rice, eaten daily by most of the world’s population. The record here notes no contraindication. It is not a herb that anyone needs to be warned off, and the practical questions around it are dietary rather than medicinal.

  • As a food — the ordinary considerations apply and are not properties of the herb: rice is a high-glycaemic carbohydrate, which matters for people managing blood glucose, and rice is known to take up inorganic arsenic from soil and water, which is why varying grains in the diet is generally advised. Neither is a Chinese-medicine caution.
  • Within a formula — the amounts involved (9–30 g of dry rice, most of which is strained out with the dregs) are dietarily trivial.
  • Coeliac disease and gluten — rice contains no gluten. It is sometimes confused with the wheat-derived medicinal Fu Xiao Mai (unripe/light wheat grain, held here as Fructus Levis Tritici Aestivi), which is a different grain entirely.
  • Not a substitute for assessment — the recorded indications, weak digestion and chronic diarrhoea among them, are symptoms that warrant proper evaluation rather than a dietary adjustment alone.

  Source: Sacred Lotus sources & references (recorded caution: none noted); dietary points per general food-science consensus, cross-referenced against multiple online sources. Reference note, not a safety guarantee.

Chinese Herb Toxicity & Overdose

• None. Rice is a staple food with no toxicity designation, no toxic constituent and no dose ceiling. The only point worth recording neutrally is an ordinary food-safety one that has nothing to do with its medicinal use: cooked rice left at room temperature can support Bacillus cereus, so cooked rice is cooled promptly and refrigerated. That is kitchen practice, not a property of the herb.

  Source: materia medica consensus, cross-referenced against multiple online sources. Reference note, not a safety guarantee.

Herb-Drug Interactions

• No herb–drug interactions are documented for Geng Mi. None would be expected for rice, and no interaction study was located. The only medication-adjacent consideration is dietary rather than pharmacological: rice is a significant carbohydrate load, which is relevant to anyone titrating insulin or other glucose-lowering medication to their meals — a nutrition matter, not a herb–drug interaction. (Flagged for practitioner confirmation.)

Western / Biomedical Research

Chinese Herb Clinical Studies & Research

Provided as research context — a summary of published biomedical study, not a therapeutic or medical claim.

• Is there modern research on Geng Mi (rice) as a Chinese herb?

  Essentially none, and it is more useful to say so plainly than to import findings from food science. There is an enormous scientific literature on rice as a crop and a food — starch chemistry, glycaemic index, resistant starch, arsenic uptake, cultivar genetics — and none of it is framed around Geng Mi’s role in Chinese medicine or tests its traditional indications. No pharmacological study of rice as a medicinal ingredient was located.

  What does exist is research on the formulas that contain it, which is the appropriate level given that the rice never acts alone:

  • Bai Hu Tang — a 2018 study isolated nanometre aggregates from a traditionally prepared Bai Hu Tang decoction, characterised them, and reported that this fraction carried a stronger antipyretic effect in animals than the other dispersion phases of the decoction, with antipyretic constituents including mangiferin and glycyrrhizic acid found within the aggregates. It is an interesting piece of work on how a whole decoction behaves as a physical system rather than as a list of compounds, though it does not isolate what the rice contributes. Separately, a 2022 systematic review and meta-analysis examined a ginseng-containing Bai Hu Tang variant combined with conventional medicine in type 2 diabetes, and a 2022 study examined the formula’s effect on endothelin-1 signalling in vascular endothelial cells.
  • Zhu Ye Shi Gao Tang — a 2022 clinical study assessed the decoction combined with another preparation in acute exacerbation of chronic obstructive pulmonary disease in a phlegm-heat pattern, and a 2017 randomised controlled trial assessed a compound Zhuye Shigao granule in acute radiation-induced oesophagitis in cancer patients. These are formula-level trials, mostly small and conducted in China, and they are cited here as context for the formulas rather than as evidence for any single ingredient.

  No study attributes an effect specifically to the rice component of any formula. The traditional rationale for including it — protecting the Stomach, generating fluids, giving the decoction body — rests on materia medica consensus and long clinical use, and has not been tested directly.

  Sources: PMID 30111786, PMC 6093970, DOI 10.1038/s41598-018-30690-5 (nanometre aggregates from a Bai-Hu-Tang decoction and their antipyretic effect); PMID 35469158, PMC 9034934, DOI 10.1155/2022/9572384 (Ginseng-plus-Bai-Hu-Tang systematic review and meta-analysis); PMID 34752899, DOI 10.1016/j.jep.2021.114812 (Bai-Hu-Tang and endothelin-1 signalling); PMID 35571736, PMC 9106455, DOI 10.1155/2022/7942623 (Zhuye Shigao Decoction in COPD acute exacerbation); PMID 28035542, DOI 10.1007/s11655-016-2652-5 (compound Zhuye Shigao granule in radiation-induced oesophagitis, randomised controlled trial). Research context, not a therapeutic claim.

Chinese Herb Notes

• Why is rice added to Bai Hu Tang and Zhu Ye Shi Gao Tang?

  Because those formulas are cold enough to hurt the stomach, and the rice is there to stop them doing it. Bai Hu Tang (White Tiger Decoction) is recorded on this site as Shi Gao (gypsum) 30 g, Zhi Mu 9 g, Zhi Gan Cao 3 g and Geng Mi 9–15 g. Gypsum is a very cold mineral and Zhi Mu is bitter and cold; taken alone they would be hard on the Middle Jiao, and in a patient with a blazing fever the digestion is already compromised. The rice and the honey-fried licorice are the formula’s protective half: sweet, moderating, fluid-generating, and buffering. Without them the formula would still clear heat, and would be far harder to take.

  Zhu Ye Shi Gao Tang (Lophatherus and Gypsum Decoction) applies the same design to the aftermath of a febrile illness — recorded here as Dan Zhu Ye, Shi Gao 30 g, Ren Shen, Mai Men Dong, Ban Xia, Zhi Gan Cao and Geng Mi 12–15 g. Here the rice does double duty: buffering the gypsum, and joining Mai Men Dong and Ren Shen in restoring the fluids and Qi that the fever consumed.

  The pattern holds across the other formulas on this site that contain it:

  • Xie Bai San (Drain the White Powder) — Geng Mi 15–30 g with Sang Bai Pi, Di Gu Pi and Zhi Gan Cao. A Lung-heat formula frequently given to children, where protecting the stomach matters most.
  • Mai Men Dong Tang (Ophiopogonis Decoction) — Geng Mi 9–15 g with Mai Men Dong, Ren Shen, Da Zao, Gan Cao and Ban Xia. A fluid-generating formula in which the rice is one of several sweet, moistening, Stomach-supporting ingredients.
  • Qing Shu Yi Qi Tang (Clear Summerheat and Augment the Qi Decoction) — Geng Mi 12–15 g in a formula of cooling, fluid-generating herbs.
  • Tao Hua Tang (Peach Blossom Decoction) — Geng Mi 30 g with Chi Shi Zhi and Gan Jiang, the largest recorded amount, in a formula for chronic dysenteric disorder where the rice nourishes a badly depleted Middle Jiao.

  What is the difference between Geng Mi, Nuo Mi and Gu Ya?

  All three come from rice, and they are not interchangeable.

  • Geng Mi (this entry) — non-glutinous rice, the ordinary short- or medium-grain table rice. Sweet, cool; Spleen and Stomach. Recorded here in the Qi-tonifying category. This is the one used in the classical decoctions above.
  • Nuo Mi — glutinous or “sticky” rice, the sort used for rice cakes and zongzi. It is sweet and warm rather than cool, and it is regarded as more strongly tonifying, more astringent and more binding — and correspondingly harder to digest and more prone to generate dampness. It is traditionally used where the aim is to consolidate and astringe rather than to cool and moisten. No separate record for Nuo Mi is held on this site, though the related medicinal Nuo Dao Gen Xu (glutinous rice root, Radix Oryzae Glutinosae) is held separately in the astringent category and is used for spontaneous and night sweating — a different part of a different rice with a different action again.
  • Gu Ya (rice sprout, held here as Fructus Germinatus Oryzae Sativae) — germinated rice, and not a food ingredient at all but a digestive. It sits in the food-stagnation category, is sweet and neutral, and mildly reduces food accumulation while strengthening the Spleen. Sprouting is what makes it a medicine; ordinary rice is not a substitute for it, and it is not a substitute for ordinary rice.

  The short version: Geng Mi is table rice used inside formulas, Nuo Mi is sticky rice and is warming, Gu Ya is sprouted rice and is a digestive.

  Formula composition flagged for review: the record for Bu Fei e Jiao Tang (Tonify the Lungs Decoction with Ass Hide Gelatin) lists Geng Mi 30 g. Most published sources give the rice ingredient of this formula as Nuo Mi (glutinous rice) rather than non-glutinous Geng Mi. Since the two rices are traditionally held to differ in nature — warm and astringent versus cool and moistening — this is a real distinction rather than a spelling variant. The formula record has been left exactly as held and is flagged here rather than changed.

  Identity fields flagged for review: (1) the Chinese characters and the tone-marked pinyin are blank in the record here; the herb is written 粽米 and is read gēng mǐ, also commonly romanised Jing Mi, since the character 粽 carries both readings. (2) The nature is recorded as cool; a number of standard materia medica give Geng Mi as sweet and neutral, or sweet and only slightly cool. The difference is small and has little practical consequence for how the herb is used, but it is noted rather than silently resolved. (3) A separate note is that our recorded companion entry Gu Ya carries its own flagged identity question over whether the name properly denotes germinated rice or germinated millet; that flag stands and is not affected by anything here.

  Source: Sacred Lotus sources & references (formula-ingredient records for Bai Hu Tang, Zhu Ye Shi Gao Tang, Mai Men Dong Tang, Xie Bai San, Qing Shu Yi Qi Tang, Tao Hua Tang and Bu Fei e Jiao Tang, with recorded amounts; herb records for Gu Ya and Nuo Dao Gen Xu; Nuo Mi confirmed absent from the herb records); cross-referenced against multiple online sources and materia medica consensus (Bensky, Materia Medica 3rd ed.; Chen & Chen).