Lian Geng (Lotus Stem)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Lian Geng?

  About 9–15 g in decoction, with published ranges starting as low as roughly 6 g. This reference's own record carries no dosage figure for the stem, but its own formula record does, and it sits squarely in that range: 12–15 g in Qing Shu Yi Qi Tang. Fresh stem, when available, is used in larger quantity than dried, as with the leaf.

  • In context: in Qing Shu Yi Qi Tang the stem's 12–15 g is among the larger amounts in the prescription, level with Shi Hu and Geng Mi at 12–15 g and behind only the watermelon rind at 24–30 g. The cooling, moistening bulk herbs carry the formula; the sharper herbs — Huang Lian at 2–3 g, Zhi Mu and Dan Zhu Ye at 4.5–6 g — are used sparingly.
  • Preparation — supplied as dried stem sections, decocted in the ordinary way; no special processing is recorded.
  • Food overlap — the lotus is a food plant throughout its length. The rhizome is a common vegetable and the young stems are eaten in parts of Southeast Asia, so this is food-adjacent material.

  Source: this reference's own formula record for Qing Shu Yi Qi Tang (composition and quantities); decoction range per published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Lian Geng?

  This reference's own record carries no cautions for Lian Geng, which is consistent with a mild, food-adjacent, neutral herb. The cautions that apply are those of its category rather than warnings specific to this material.

  • Summerheat herbs are for heat, not for cold. A herb whose purpose is to clear summer heat has no place in a cold, deficient pattern, where it will further weaken the digestion. Match the season and the pattern, not the calendar.
  • Spleen and Stomach deficiency with loose stools — the general caution for cooling, damp-clearing herbs; the stem is neutral rather than cold, so this is a mild caution.
  • Heatstroke is a medical emergency. The Summerheat category overlaps in name with genuine heat illness. Confusion, collapse, a very high temperature or a person who has stopped sweating in the heat needs emergency care, not a decoction. This entry is reference information about a traditional herb.
  • Pregnancy and breastfeeding — no specific traditional prohibition is recorded for the stem, but herbal use in pregnancy belongs with a qualified practitioner.
  • Athletes subject to anti-doping testing should read the toxicity note below before using any lotus-derived product.

  Source: this reference's own record (no cautions recorded for this herb); category cautions per published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources. Reference note, not a safety guarantee.

Chinese Herb Toxicity & Overdose

• Low. Lotus stem is food-adjacent material from a plant eaten throughout Asia, and no significant toxicity is reported for it in the traditional literature at customary doses; this reference's own record notes none. The modern work on this part is chemical and preclinical rather than toxicological.

  On higenamine and anti-doping, specifically for the stem — and this one has to be reported carefully. This reference's Lian Zi Xin entry records that the lotus plumule contains higenamine, a beta-agonist compound prohibited by the World Anti-Doping Agency since 2017, and its Lian Xu entry records that in a UPLC/QToF-MS comparison of the six lotus parts listed in the Chinese Pharmacopoeia — seed, leaf, plumule, stamen, receptacle and rhizome node — higenamine was assigned to the leaf and plumule only (PMID 33806084, PMC 8036816). The stem was not one of the six parts examined in that study, and no study was located in PubMed or PMC that measures higenamine in lotus stem or petiole either way. A review of higenamine-containing plants written for the anti-doping question names Nelumbo nucifera as a source plant without identifying which part is responsible (PMID 35161335, PMC 8838985).

  So the honest position for the stem is not established, and unlike the stamen it should not be assumed clear. The stem is the petiole — anatomically continuous with the leaf, which is one of the two parts where higenamine is documented — and phytochemical work on lotus leaves and stems has treated them together as a single source material (PMID 36058474). That makes silence in the literature a weaker reassurance here than it was for the stamen. Absence of findings is not proven absence. Athletes subject to testing should treat any lotus-derived product as a potential risk and check with their anti-doping authority before use.

  Source: PMID 33806084, PMC 8036816 (Molecules 2021, DOI 10.3390/molecules26071855 — six lotus parts compared; stem not among them); PMID 35161335, PMC 8838985 (Plants 2022, DOI 10.3390/plants11030354); PMID 36058474 (Fitoterapia 2022, DOI 10.1016/j.fitote.2022.105294 — leaves and stems studied together); this reference's own Lian Zi Xin and Lian Xu records. Reference note, not a safety guarantee.

Herb-Drug Interactions

• Does Lian Geng interact with medications?

  No herb–drug interactions have been documented for lotus stem. There are no clinical interaction reports and no pharmacokinetic studies on this part of the plant. Absence of documented interactions is not evidence of safety — it reflects how little the stem has been studied separately from the leaf.

  • Do not read across from the plumule, but do not assume total separation either. The interaction concerns that exist for the lotus centre on neferine and higenamine, both concentrated in the plumule. Neither has been reported as a stem constituent — but neither has the stem been specifically tested, and it is continuous with the leaf, where higenamine is documented. Anyone taking beta-blockers, beta-agonists or cardiac medication should raise any lotus-containing formula with their prescriber.
  • Patients taking prescription medication should tell their prescriber about any herbal formula they are using. Flagged for practitioner confirmation.

  Source: PMID 33806084, PMC 8036816 (part-specific constituent assignment); no interaction studies located in PubMed/PMC for this herb. Reference information only, not medical advice.

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 Lian Geng (lotus stem, Nelumbinis Caulis)?

  Some, and one animal study lines up unusually well with the traditional indication — but there is no clinical evidence, and the stem remains among the least-studied parts of a heavily studied plant. An ethanol extract of Nelumbo nucifera stalks lowered body temperature in rats, both at normal temperature and in yeast-induced fever, with a dose-dependent effect at 200 and 400 mg/kg that the authors compared to a standard antipyretic (PMID 10861971). For a herb classed among the Summerheat-clearing medicinals, that is a suggestive finding — and it is a rodent study from 2000, not evidence of an effect in people.

  • The stalks have been assayed alongside the other parts. Two studies of aqueous extracts of sacred lotus included leaf stalk and flower stalk among the parts compared, measuring phenolic content, antioxidant capacity and inhibition of enzymes relevant to Alzheimer's disease, hypertension, obesity and diabetes. In both, the stamen was the standout and the stalks were more modest performers — a useful, unglamorous result that establishes the stalks are chemically real but not the plant's richest tissue (PMID 32824050, PMC 7463813; PMID 37050065, PMC 10097295). The second also found the values shift substantially with harvest season.
  • Compounds isolated from stems — phytochemical work on the leaves and stems of edible lotus isolated eighteen compounds including two new ones (a butanedione glycoside and a eudesmane-type sesquiterpenoid) and screened them for effects on osteoclast formation; two suppressed RANKL-induced osteoclast formation in a cell assay (PMID 36058474). Cell-level work, and the leaves and stems were extracted together.
  • Part-specific chemistry of the plant — the UPLC/QToF-MS comparison of the six Pharmacopoeia lotus parts characterised 171 compounds and showed the parts are chemically separable and should not be treated as interchangeable (PMID 33806084, PMC 8036816). The stem was not included among those six, which is itself the clearest statement of how thinly it has been studied.

  Taken together: the lotus stem has one traditionally congruent animal finding (antipyretic), a place in comparative phenolic surveys of the plant, and some isolated compound chemistry shared with the leaf. There are no human trials of Lian Geng, and nothing above should be read as a therapeutic claim.

  Sources: PMID 10861971 (Phytother Res 2000); PMID 32824050, PMC 7463813 (Molecules 2020, DOI 10.3390/molecules25163713); PMID 37050065, PMC 10097295 (Plants 2023, DOI 10.3390/plants12071441); PMID 36058474 (Fitoterapia 2022, DOI 10.1016/j.fitote.2022.105294); PMID 33806084, PMC 8036816 (Molecules 2021, DOI 10.3390/molecules26071855). Research context, not a therapeutic claim.

Chinese Herb Notes

• How is Lian Geng different from the other lotus medicinals?

  Lian Geng is the connecting one — the part whose job is to open a passage. Where He Ye (the leaf) clears Summerheat, Lian Zi Xin (the plumule) drains Heart fire and Lian Xu (the stamen) binds and secures, the stem unblocks: it takes the leaf's cooling, Summerheat-clearing character and directs it at a chest that feels stuffed and a middle burner that feels stuck. It is the least famous of the seven and the most specific.

  The lotus plant (Nelumbo nucifera) in the materia medica — the seven medicinals this reference holds, each with its own name, part and action:

  • He Ye (Lotus Leaf) — the leaf; clears Summerheat, raises clear yang, and (charred) stops bleeding.
  • Lian Zi (Lotus Seed) — the seed; tonifies Spleen and Kidney, stabilizes the essence, and calms the Heart.
  • Lian Zi Xin (Lotus Plumule) — the green embryo inside the seed; drains Heart fire and calms the spirit.
  • Ou Jie (Node of the Lotus Rhizome) — the rhizome node; stops bleeding, especially of the upper body.
  • Lian Geng (Lotus Stem) — this herb; the stem; clears Summerheat and unblocks qi circulation in the chest and diaphragm.
  • Lian Fang (Mature Lotus Receptacle) — the seed-pod receptacle; used for bleeding.
  • Lian Xu (Lotus Stamen) — the flower stamens; astringes the Kidneys and secures the essence.

  Lian Geng and He Ye are the closest pair. This reference gives them identical properties (bitter, slightly sweet, neutral), identical channels (Heart, Liver, Spleen) and the same category, which is unusual for two parts of one plant and is a deliberate statement: they do the same work. The leaf is the broader Summerheat herb and the one used charred for bleeding; the stem is chosen when the same Summerheat pattern comes with a blocked, oppressed chest. Anatomically they are continuous — the stem is the petiole that holds the leaf up — which is the simplest way to remember why they behave alike.

  Which formulas use Lian Geng?

  In this reference's own formula records Lian Geng appears in Qing Shu Yi Qi Tang (Clear Summerheat and Augment the Qi Decoction), from Warp and Woof of Warm Febrile Diseases (Wen Re Jing Wei). This is exactly the formula the herb's profile predicts: a prescription for Summerheat that has damaged both the qi and the fluids, built from watermelon rind, Xi Yang Shen, Shi Hu, Mai Men Dong, Zhi Mu, Dan Zhu Ye, a small amount of Huang Lian, Gan Cao and Geng Mi. Lian Geng at 12–15 g is there to clear the summer heat while keeping the chest and middle burner open, so that the sweet, moistening, fluid-generating herbs around it do not clog a digestion already burdened by summer damp. (Traditional formula context, not treatment advice.)

  Data note — missing Chinese characters. This reference records no Chinese name for Lian Geng; the field is empty. The expected forms are 莲梗 (Lian Geng) or, as the same material is more often written in formula texts, 荷梗 (He Geng). The Latin recorded here, Nelumbinis Caulis, confirms the substance is the lotus stem. Left unchanged pending owner confirmation and flagged for the data-quality list.

  Source: this reference's own records for the lotus-derived herbs and for Qing Shu Yi Qi Tang (identity, properties, channels, categories, formula composition and quantities); differentiation per published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources.