Yu Zhu (Solomon's Seal Rhizome, Polygonatum)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Yu Zhu?

  Roughly 6–15 g in decoction. Sacred Lotus sources give 10–15 g (Chen) and 6–15 g (Bensky) — a fairly wide standard range reflecting its gentle, non-cloying nature, which allows for somewhat higher doses than heavier yin tonics when stronger moistening is needed.

  Source: Sacred Lotus sources & references; cross-referenced against multiple online sources for standard materia medica dosage ranges. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Yu Zhu?

  Sacred Lotus sources note Yu Zhu should be avoided in loose stools due to cold, and more broadly in Spleen or Stomach deficiency, Phlegm-Damp, Phlegm stagnation, and Qi stagnation. Although less cloying than many yin tonics, its moistening, slightly cold nature is still not well suited to a cold, damp, or stagnant digestive picture.

  Source: Sacred Lotus sources & references; cross-referenced against multiple online sources for standard materia medica cautions.

Chinese Herb Toxicity & Overdose

• Low, with mild reactions reported at overdose. Sacred Lotus sources note that overdose may lead to mild reactions including nausea, vomiting, or diarrhea, as well as pruritus or a papular rash. At standard decoction doses it is generally well tolerated. Reference note, not a safety guarantee.

  Source: Sacred Lotus sources & references; cross-referenced against multiple online sources.

Herb-Drug Interactions

• No well-established clinical herb–drug interactions are documented. Given preclinical research showing Polygonatum odoratum polysaccharides can lower blood glucose (below), practitioner awareness is reasonable for patients on glucose-lowering medication — this is precautionary, not a demonstrated clinical 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 Yu Zhu (Polygonatum odoratum)?

  Yes — an active and growing body of preclinical research, mostly on its polysaccharides, with no located human clinical trials to date. Polygonatum odoratum polysaccharides (POPs) are the most-studied active fraction.

  • Blood glucose (preclinical) — a structurally distinct neutral polysaccharide isolated from the rhizome improved diet/streptozotocin-induced hyperglycemia in mice via the PI3K-AKT-GSK3β/FoxO1 signaling pathway, supporting glycogen synthesis and lowering blood glucose; animal research.
  • Gut microbiota & metabolic health (preclinical) — POPs reduced weight gain, fat accumulation, and liver triglycerides/cholesterol in high-fat-diet rats, associated with favorable shifts in gut bacterial populations and increased short-chain fatty acids; animal research.
  • Lung protection (preclinical) — POPs improved survival, lung function, and inflammatory markers in a lipopolysaccharide-induced acute lung injury mouse model, again linked to gut-microbiota changes; animal research.
  • Anticancer lectin activity (preclinical) — a lectin isolated from Polygonatum odoratum induced apoptosis and autophagy in human MCF-7 breast cancer cells via the EGFR/Ras-Raf-MEK-ERK pathway; cell-based laboratory research, not a treatment claim.

  All findings are preclinical (cell or animal models); human clinical evidence for Yu Zhu specifically was not located.

  Sources: PMID 41344518 (hyperglycemia/polysaccharide, Journal of Ethnopharmacology); PMID 30428630 (gut microbiota/obesity, International Journal of Molecular Sciences); PMID 37970373 (lung injury/polysaccharide, Food Science & Nutrition); PMID 25442274 (lectin/breast cancer cells, Phytomedicine). Research context, not a therapeutic claim.

Chinese Herb Notes

• How is Yu Zhu different from Huang Jing (Polygonatum sibiricum)?

  Yu Zhu and Huang Jing are related Polygonatum species but are used quite differently — Yu Zhu is the lighter, cooler, more specifically Lung/Stomach-yin herb, while Huang Jing is a heavier, warmer, broader Qi-and-Yin tonic. Yu Zhu (Polygonatum odoratum) is sweet and slightly cold, targets Lung and Stomach yin and fluid damage from febrile disease, and is prized for not being cloying. Huang Jing (Polygonatum sibiricum, Siberian Solomon’s Seal) is sweet and neutral, tonifies Spleen Qi as well as Lung and Kidney yin, is more broadly tonifying (and more cloying) for general deficiency and fatigue, and has a longer history as a Daoist longevity/nourishing substance. They are not interchangeable despite the shared genus and similar-sounding names.

  Common combinations: Yu Zhu is a key herb in Jia Jian Wei Rui Tang (Augmented Solomon’s Seal Decoction), a formula for wind-warmth invading the exterior in a patient with underlying yin deficiency — fever, slight chills, headache, cough, and a dry mouth and throat. There, Yu Zhu’s non-cloying nourishment of yin is precisely what allows the formula to release the exterior without further damaging fluids, while the wind-release does not dry out the yin further. (Traditional formula context, not treatment advice.)

  Source: Sacred Lotus sources & references (formula link); cross-referenced against multiple online sources for materia medica differentiation.