Deng Xin Cao
StarJuncus effusus L.
Traditionally used for
- Nose & throat
- Urinary & fluids
- Sleep
- Mood & calm
- Energy & fatigue
Cautions & contraindications
- Pregnancy
- Young children
- Kidney conditions
☯ TCM Properties
Clears Heart Fire; Promotes Urination and Relieves Stranguria; Promotes Quality Sleep; Clears Heat and reduces swelling of the throat
Traditional Chinese Uses
Deng Xin Cao (juncus pith) is a light, sweet, cold herb that clears mild Heat from the Heart and Small Intestine and promotes urination. It is used for restlessness, insomnia from mild Heart Heat, and urinary discomfort including scanty, burning, or dark urination from Heat accumulation. Its gentle, mild character makes it appropriate as a daily herb for heat-type restlessness and minor urinary complaints in patients who need a light rather than aggressive Heat-clearing approach.
Western Herbalism Properties
Traditional Uses
Juncus effusus is documented in the NAEB database with twenty recorded uses across Cherokee, Mendocino, and other peoples; six are medicinal (Drug class), mostly for emetic, oral aid, orthopedic aid, pediatric aid, strengthener, and unspecified applications, with the remainder being fiber and basketry use (NAEB).
Used In Formulas (2)
Relationships
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Botanical Description
Juncus effusus, soft rush or Deng Xin Cao, is a tufted perennial graminoid in the Juncaceae family with a near-global distribution in wet meadows, marshes, ditches, and stream margins. Plants form dense clumps 60-150 cm tall of slender, cylindrical, smooth, glossy green stems 1.5-3 mm thick, with no obvious leaves above the basal sheaths. The inflorescence appears as a lateral cluster of small greenish-brown flowers a few centimeters below the apparent stem tip; the structure above is actually a continuing involucral bract. Stems are harvested in late summer and the soft white inner pith is teased out and dried for medicinal use.
Active Constituents
Dehydroeffusol
PhenanthreneConcentration: Isolated from the medulla by bioactivity-guided fractionation; no validated content figure has been published for the commercial drug
The best-characterised constituent of the pith. It enhances GABA-induced chloride current at recombinant alpha1beta2gamma2S GABA-A receptors by up to 239 percent, independently of the benzodiazepine binding site, and is anxiolytic and sedative in mice from 2.5 mg/kg without impairing motor coordination.
Effusol
PhenanthreneConcentration: Co-isolated with dehydroeffusol from the pith; content in the crude drug not established
A second positive allosteric modulator of the GABA-A receptor from the same pith fraction, enhancing GABA-induced chloride current by up to 188 percent; together with dehydroeffusol it provides the only mechanistic account of the herb's traditional sedative use.
Dehydroeffusal
Phenanthrene aldehydeConcentration: Minor constituent described from the medullae
One of two new phenanthrene derivatives first characterised from the medullae of Juncus effusus; no independent pharmacology has been published for it.
Juncusol and phenanthrenoid dimers
Phenanthrenes and phenanthrenoid dimersConcentration: Minor constituents of the medulla
Phenanthrenes isolated from the medullae show cytotoxic and anti-inflammatory activity in cell assays. This is exploratory chemistry rather than a basis for clinical claims.
⚠ Drug Interactions
Benzodiazepines, z-drugs, barbiturates, sedating antihistamines and alcohol
Effusol and dehydroeffusol, isolated specifically from Junci Medulla (the pith), are positive allosteric modulators of the alpha1beta2gamma2S GABA-A receptor in two-microelectrode voltage clamp, enhancing GABA-induced chloride current by 188 and 239 percent respectively; the effect is independent of the benzodiazepine binding site, so it can add to benzodiazepine action rather than compete with it. Dehydroeffusol is anxiolytic and sedative in mice from 2.5 to 5 mg/kg. All evidence is preclinical; no human pharmacokinetic or interaction study of the drug exists, and the customary clinical dose (1-3 g of an extremely light material) may not deliver a pharmacologically relevant amount.
Clinical note: Reasonable to mention when Deng Xin Cao is prescribed for insomnia to a patient already on a sedative-hypnotic. Watch for excess drowsiness rather than assuming none; do not treat the herb as a substitute for adjusting the prescribed hypnotic.
Cinnabar (Zhu Sha, mercuric sulfide) in the processed form Zhu Deng Xin
For the spirit-calming indication the pith is traditionally coated with cinnabar to give Zhu Deng Xin (cinnabar-dusted rush pith). Cinnabar is mercuric sulfide, and the resulting drug is a mercury-containing preparation regardless of how little Deng Xin Cao itself contributes. This monograph describes the plain, unprocessed pith; the cinnabar-processed form has a different and materially worse safety profile.
Clinical note: Confirm which form the pharmacy has supplied. Avoid the cinnabar-coated form in children, in pregnancy, in renal impairment, and wherever mercury-containing herbal products are restricted; the plain pith carries none of this risk.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 1–3 g | Daily | — | — | 中国药典 2020 【用法与用量】1~3g。 【性味与归经】甘、淡,微寒。归心、肺、小肠经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Evidence Tier
Moderate evidence · 4 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
0
In vitro / animal
4
2 verified · 2 unverified
Show 4 studies
- GABAA Receptor Modulators from the Chinese Herbal Drug Junci Medulla - The Pith of Juncus effusus
- Anxiolytic and Sedative Effects of Dehydroeffusol from Juncus effusus in Mice
- Phenanthrenes from Juncus effusus with anxiolytic and sedative activities
- Cytotoxic and anti-inflammatory activities of phenanthrenes from the medullae of Juncus effusus L.
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
GABAA Receptor Modulators from the Chinese Herbal Drug Junci Medulla - The Pith of Juncus effusus
Bioactivity-guided isolation from the pith itself, rather than the whole plant, yielded effusol and dehydroeffusol, both of which concentration-dependently enhanced GABA-induced chloride currents at recombinant GABA-A receptors by 188 and 239 percent, independently of the benzodiazepine site. The most directly relevant mechanistic study of the actual drug.
Anxiolytic and Sedative Effects of Dehydroeffusol from Juncus effusus in Mice
Dehydroeffusol increased open-arm entries and time in the elevated plus-maze from 2.5 mg/kg and head-dips in the hole-board test from 5 mg/kg, and reduced open-field locomotion from 5 mg/kg, while 1-5 mg/kg left rota-rod performance intact. Anxiolytic and sedative without gross motor impairment, in mice.
Phenanthrenes from Juncus effusus with anxiolytic and sedative activities
Extends the anxiolytic and sedative behavioural profile beyond dehydroeffusol to further phenanthrenes of the species. Preclinical; no dose has been tested in humans.
Cytotoxic and anti-inflammatory activities of phenanthrenes from the medullae of Juncus effusus L.
Phenanthrenes isolated from the medullae showed cytotoxic and anti-inflammatory activity in cell assays. Relevant to the chemistry of the pith, but far from any clinical claim.
Historical Texts
Kai Bao Ben Cao (Materia Medica of the Kaibao Reign Period)
Northern Song dynasty, c. 973-974 CEBen Cao Gang Mu (Compendium of Materia Medica), Li Shizhen
Ming dynasty, 1596References
- Shima K, Toyota M, Asakawa Y. Phenanthrene derivatives from the medullae of Juncus effusus . Phytochemistry (1991) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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