Chong Wei Zi (Motherwort Seeds)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Chong Wei Zi?

  Roughly 4.5–9 g in decoction, with some published sources extending the range to about 10 g. This reference's own record carries no dosage figure for the seed, so the range given here is the published materia medica consensus rather than a site figure. It is a small dose — smaller than for the aerial part of the same plant, which is commonly given at several times this weight.

  • There is a dose ceiling, and it matters. Published materia medica describe an adverse reaction to large single doses of the seed — conventionally placed at around 30 g and above — presenting as sudden weakness, generalised aching, profuse sweating and heaviness or weakness of the legs. This is one of the few herbs in the collection with a specific quantitative ceiling attached, and it is the reason the recommended range is kept narrow. See the toxicity note below.
  • Preparation — the seeds are hard and are commonly crushed before decoction so that the constituents can be extracted.
  • Not interchangeable with Yi Mu Cao by weight. Substituting one for the other at the other's dose is a real risk with this pair, because the names, the plant and the gynaecological indications overlap. They are separate medicinals with separate ranges.

  Source: published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources; this reference's own record carries no dosage figure for this herb. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Chong Wei Zi? Is it safe in pregnancy?

  Use strict caution in pregnancy — this reference's own recorded caution, and the one that matters most. Chong Wei Zi is a blood-invigorating herb from a plant whose aerial part is a recognised uterine stimulant, and the whole category is traditionally restricted or avoided in pregnancy. This reference records the same strict-caution wording for its sibling Yi Mu Cao, so the caution is consistent across both parts of the plant.

  The other cautions carried in this reference's own record:

  • Do not use in blood-deficient or yin-deficient patients — a moving, draining herb given into depletion aggravates it.
  • Do not use in yang-deficient patients with prolapse — where the pattern is qi failing to hold things up, a downward-moving herb works against the treatment.

  Beyond the record:

  • Observe the dose ceiling. Unlike most herbs in this collection, the seed has a specific quantity associated with adverse reactions in the published literature (see the toxicity note). This is a herb to use inside its range, under supervision.
  • Heavy or irregular bleeding needs assessment. Amenorrhoea, abnormal bleeding, postpartum pain and sudden eye pain or redness all have medical causes that require diagnosis. This entry is reference information about a traditional herb, not guidance for self-treatment; acute painful red eye in particular is a same-day medical matter.

  Source: this reference's own cautions record for Chong Wei Zi and its own Yi Mu Cao record; 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

• Chong Wei Zi is one of the small number of otherwise ordinary herbs that carries a documented large-dose adverse reaction. Published materia medica describe a reaction to large single doses of the seed — conventionally set at approximately 30 g and above — appearing some hours after ingestion as sudden generalised weakness, aching or pain through the body, profuse sweating, and weakness or a paralysed feeling in the lower limbs, with the lower body sometimes described as sweating while sensation is preserved. The reaction is reported as self-limiting once the herb is stopped. It is recorded here as a neutral reference fact and as the reason the recommended dosage range is narrow; it is not a usage instruction, and the herb belongs in the hands of a qualified practitioner.

  The modern literature adds little that is seed-specific. A review of adverse renal effects associated with Leonurus preparations exists but concerns the plant and its aerial part rather than the seed (PMID 20707084). In a zebrafish embryo assay, motherwort alkaloids showed an angiogenic effect while the essential oil of the plant was toxic to the embryos — a laboratory observation about the whole plant's essential oil, not about the dried seed in a decoction (PMID 29729400). A broad review of Leonurus japonicus summarises the toxicological literature for the species and concludes that systematic safety evaluation is still incomplete (PMID 24412548).

  Sourcing note: the 30 g figure and the described reaction come from the Chinese materia medica literature as summarised in the standard English-language references, not from an indexed case series that could be cited here directly. It is consistent across those references and is therefore retained, but the underlying case reports could not be verified individually and the threshold should be treated as a conventional figure rather than a measured one.

  Source: published materia medica consensus (Bensky, Materia Medica, 3rd ed.; Chen & Chen, Chinese Medical Herbology and Pharmacology), cross-referenced against multiple online sources; PMID 20707084 (Zhongguo Zhong Yao Za Zhi 2010, renal adverse reactions, aerial part); PMID 29729400 (Fitoterapia 2018, DOI 10.1016/j.fitote.2018.05.002); PMID 24412548 (J Ethnopharmacol 2014, DOI 10.1016/j.jep.2013.12.052). Reference note, not a safety guarantee.

Herb-Drug Interactions

• Does Chong Wei Zi interact with medications?

  No herb–drug interactions have been documented for Chong Wei Zi specifically. No clinical interaction reports and no pharmacokinetic studies on the seed were located. Absence of documented interactions is not evidence of safety here — it reflects how little the seed has been studied separately from the aerial part.

  • Theoretical caution — anticoagulants and antiplatelet drugs. Blood-invigorating herbs as a class are conventionally used with care alongside warfarin, direct oral anticoagulants, antiplatelet agents and around surgery. This is a category-level, mechanism-based caution rather than a reported interaction for this herb.
  • Theoretical caution — pregnancy and uterotonic medication. Given the plant's traditional uterine action and the strict pregnancy caution recorded for this herb, use around pregnancy, labour or any uterotonic treatment belongs entirely with the treating clinicians.
  • Patients taking prescription medication should tell their prescriber about any herbal formula they are using. Flagged for practitioner confirmation.

  Source: category-level cautions per published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources; 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 Chong Wei Zi (motherwort seed, Leonurus japonicus)?

  Very little on the seed by itself — most published work on this plant concerns the aerial part, Yi Mu Cao. What seed-specific research exists is chemical, plus one clinically studied eye formula that contains it. A comprehensive review of Leonurus japonicus covers the species' ethnopharmacology, phytochemistry and pharmacology, including its alkaloids leonurine and stachydrine, and is the standard reference point for the plant's evidence base (PMID 24412548). It is not, however, a review of the seed.

  • The seed is chemically distinguishable from the herb. A thin-layer chromatography–mass spectrometry method was developed expressly to characterise the differences and similarities between Leonuri Herba (the aerial part) and Leonuri Fructus (the seed), using an improved alkaloid staining reagent (PMID 32559000). Earlier phytochemistry isolated a cyclic peptide, cycloleonurinin, from the seed material specifically (PMID 2070452).
  • The eyes: the one place the seed appears in clinical research. Qiming granules, a Chinese proprietary formula for diabetic retinopathy, contains Fructus Leonuri among eight ingredients (PMID 36332761). A systematic review and meta-analysis pooled 33 randomised controlled trials involving 3,042 patients and reported benefit for the formula on overall efficacy, visual acuity and macular thickness, with fewer adverse events in the treatment arms — while rating the certainty of evidence as no better than moderate and noting the general limitations of the underlying trials (PMID 39239647, PMC 11374745). This is evidence about a multi-herb proprietary formula, not about Chong Wei Zi taken alone, and it is included here because it is the only clinical literature in which the herb features.
  • Species-level pharmacology — leonurine, the plant's characteristic alkaloid, has been reviewed as an agent with effects reported well beyond gynaecology in preclinical models (PMID 31069695), and stachydrine has its own pharmacological and pharmacokinetic review (PMID 32173585). Both compounds occur across the genus and neither is unique to the seed.

  Taken together: the seed is chemically characterised and analytically separable from the aerial part, and it appears in one proprietary eye formula with a meta-analysed but moderate-certainty clinical literature. There are no trials of Chong Wei Zi alone for any indication, and nothing above is a therapeutic claim.

  Sources: PMID 24412548 (J Ethnopharmacol 2014, DOI 10.1016/j.jep.2013.12.052); PMID 32559000 (Phytochem Anal 2021, DOI 10.1002/pca.2970); PMID 2070452 (Chem Pharm Bull 1991, DOI 10.1248/cpb.39.712); PMID 36332761 (J Ethnopharmacol 2023, DOI 10.1016/j.jep.2022.115861); PMID 39239647, PMC 11374745 (Front Pharmacol 2024, DOI 10.3389/fphar.2024.1429071); PMID 31069695 (Chin J Integr Med 2020, DOI 10.1007/s11655-019-3453-0); PMID 32173585 (Pharmacol Res 2020, DOI 10.1016/j.phrs.2020.104755). Research context, not a therapeutic claim.

Chinese Herb Notes

• What is the difference between Chong Wei Zi and Yi Mu Cao?

  Same plant, different parts, and the difference is the eyes. Both come from Leonurus japonicus, Chinese motherwort, and both move blood in gynaecological patterns — but the aerial part is the major postpartum and menstrual herb, while the seed is the milder blood-mover that also cools the Liver and treats the eyes. This reference holds both as separate entries.

  • Yi Mu Cao (Chinese Motherwort, aerial part) — Herba Leonuri; spicy, bitter, slightly cold; Heart, Liver, Bladder and Pericardium. The classic blood-invigorating gynaecological herb: amenorrhoea, painful and irregular periods, and above all the postpartum period, where it moves lochia and relieves pain. It also promotes urination and reduces swelling — a Bladder-channel action the seed does not share — and is used for skin lesions.
  • Chong Wei Zi (Motherwort Seed) — this herb; Semen/Fructus Leonuri; sweet, cool; Liver only. Moves blood and regulates menses more gently, and adds the action the aerial part lacks: clearing and cooling the Liver to brighten the eyes, for red painful eyes and headache.

  The clean way to hold the pair: the herb is for the uterus, the seed leans toward the liver and the eyes. Their shared blood-moving action means the two overlap in menstrual patterns, but they are not substitutes for one another in formula design, and their doses differ.

  Not the same as Western "motherwort." As this reference's Yi Mu Cao record already notes, the herb of European and North American herbalism sold under the name motherwort is Leonurus cardiaca, a different species in the same genus, with its own separate tradition of use (largely cardiac and nervine rather than gynaecological). The two species share some alkaloids — stachydrine is present in both and has been quantified side by side (PMID 24704554) — but evidence and dosing for one should not be read across to the other.

  Which formulas use Chong Wei Zi?

  None of the formulas held in this reference list Chong Wei Zi among their ingredients — confirming an earlier audit note about this herb. Its sibling Yi Mu Cao appears in one formula here (Tian Ma Gou Teng Yin). The seed is characteristically used as a modification added to a base prescription, or in eye formulas outside the classical canon, rather than as a named ingredient in the formulas this collection carries.

  Outside the classical canon it is a named ingredient of at least one modern proprietary preparation with a substantial clinical literature: Qiming granules, a Chinese patent formula for diabetic retinopathy whose composition includes Fructus Leonuri alongside astragalus, kudzu, rehmannia, goji, cassia seed, typha pollen and leech (PMID 36332761). That the seed earns a place in an eye formula rather than a gynaecological one is a neat modern confirmation of the traditional "brightens the eyes" action. (Traditional and proprietary formula context, not treatment advice.)

  Data note — incomplete channel field. This reference records the channels for Chong Wei Zi as "Liver, Unknown". The second entry is a placeholder rather than a channel, and should either be resolved or removed. Published materia medica most commonly assign the seed to the Liver channel, with some sources adding the Pericardium. Left unchanged pending owner confirmation and flagged for the data-quality list.

  Nomenclature note. The Latin recorded here is Semen Leonuri ("motherwort seed") and the common name is "Motherwort Seeds". Botanically the material is the plant's dried ripe fruit — a nutlet — and the pharmacopoeial and research literature generally calls it Fructus Leonuri or Leonuri Fructus (PMID 32559000; PMID 2070452). This is a seed-versus-fruit naming convention rather than a different substance, and both names are in common use; noted for completeness, no field changed.

  Source: this reference's own records for Chong Wei Zi and Yi Mu Cao (identity, properties, channels, categories, recorded actions) and a check of its own formula records; species distinction per PMID 24412548 and PMID 24704554; Qiming granule composition per PMID 36332761; part nomenclature per PMID 32559000 and PMID 2070452; differentiation per published materia medica consensus (Bensky, 3rd ed.; Chen & Chen), cross-referenced against multiple online sources.