Jing Da Ji (Peking Spurge Root)

Chinese Herb Actions

Chinese Herb Dosage

• What is the dosage of Jing Da Ji?

  We do not publish a dose for Jing Da Ji, and our own record carries no dosage figure for it. It is a toxic, drastic purgative with a narrow margin between an effect and an injury, it is never used as raw material, and any legitimate use is a prescribing decision made by a licensed practitioner for an individual patient. Printing a number here would invite exactly the self-administration the toxicology literature documents the harm of.

  What can be stated as neutral reference fact:

  • The raw root is not used as-is. Pharmacopoeial practice requires the root to be processed before any internal use. We note that processing exists and is mandatory — not how it is done.
  • It is not decocted in the ordinary way. In the classical formulas that contain it, the water-expelling members are not boiled together with the rest of the ingredients. That is a structural fact about the formulas, not a preparation instruction.
  • Use is short and exceptional. Harsh expellants were used for a brief, decisive intervention in a strong patient, never as ongoing therapy.
  • The finished material is not interchangeable with the raw. A 2025 experimental study of Shi Zao Tang compared the decoction made with pharmacopoeially processed water-expelling roots against the unprocessed version in rats with malignant ascites: the processed version retained the fluid-clearing effect while showing measurably lower intestinal toxicity. Any published reference figure applies to the finished processed material only.

  Sources: our own herb record (no dosage held); materia medica consensus on the harsh-expellant category, cross-referenced against multiple online sources; PMID 41044610, PMC 12495871, DOI 10.1186/s13020-025-01224-9 (Chinese Medicine, 2025 — toxicity reduction with efficacy preservation in malignant ascites rats). Reference facts only, not a prescription and not a preparation guide.

Chinese Herb Contraindications & Cautions

• Is Jing Da Ji safe, and who must not use it?

  Jing Da Ji is not a safe herb by any ordinary reading of the word. It is classified toxic in its own identity record here, it is flagged in our toxic/restricted group, it is a drastic purgative, and our record states plainly: do not use during pregnancy. It is documented here for completeness of the materia medica record and for exam study, not because it is a substance a reader should seek out.

  • Contraindicated in pregnancy — stated in our own record, and consistent with the harsh-expellant category as a whole, which is withheld in pregnancy without exception.
  • Contraindicated in deficiency — the classical requirement is a genuinely strong constitution with a true excess accumulation. In a weak patient the purgation is itself the injury.
  • Not to be combined with Gan Cao (licorice) — one of the classical Eighteen Incompatibilities, and a pair our own incompatibility records hold. See the toxicity and interactions sections for what modern work has actually measured.
  • Never in raw form — the unprocessed root is a direct gastrointestinal irritant; pharmacopoeial practice excludes it from internal use.
  • Identity and sourcing matter here more than usual — a 2024 study developed combined DNA-barcode and chromatographic methods specifically to distinguish authentic Euphorbiae Pekinensis Radix from counterfeit and adulterated material, which tells you that substitution in this supply chain is a documented, not theoretical, problem.
  • Professional-only — any legitimate use belongs to a licensed practitioner working with correctly processed pharmacopoeial material in an appropriate clinical setting.

  Note: our record additionally states that this herb “has been shown to cause teratogenic (birth defects) effects.” We could not locate a resolvable published study demonstrating teratogenicity for Euphorbia pekinensis, so we have not repeated that specific claim as sourced fact. The pregnancy contraindication itself is well established and stands on its own. The existing wording is left unchanged and flagged for owner review.

  Sources: our own identity, caution and incompatibility records; PMID 39205630, DOI 10.1080/14786419.2024.2397554; PMID 39109414, DOI 10.1002/bmc.5978 (Biomedical Chromatography, 2024 — identification of Euphorbiae Pekinensis Radix and its counterfeit and adulterated products). Cross-referenced against multiple online sources. Neutral safety reference, not usage instructions.

Chinese Herb Toxicity & Overdose

• High, and mechanistically well characterised. The toxicity of Jing Da Ji and its purgative effect come from the same chemistry — the effect and the harm are not separable. Documented targets are the gastrointestinal tract first, then the liver and kidney on repeated exposure.

  What the toxicology literature documents:

  • Severe diarrhoea by an identified molecular pathway. A 2026 study in the British Journal of Pharmacology identified specific glycosphingolipids in Euphorbia pekinensis, including a previously undescribed hexosylceramide, as the primary agents of its intestinal toxicity. These act as direct agonists of the TRPA1 ion channel on intestinal enterochromaffin cells, triggering calcium influx and excessive serotonin release, which in turn causes abnormal smooth-muscle contraction and epithelial hypersecretion — that is, the severe diarrhoea. It is unusual to have the mechanism of a classical purgative mapped this precisely.
  • Liver and kidney injury on repeated dosing. In rats given the total diterpenes of the root by gavage for four weeks, hepatic and renal biochemical markers rose three- to four-fold with matching histopathological injury, alongside disruption of gut flora and of bile-acid metabolism. The study was designed around a protective co-treatment, but the injury it set out to protect against is the finding of interest here.
  • Intestinal injury is dose- and preparation-dependent. Comparative work on Shi Zao Tang found the pharmacopoeially processed version produced less intestinal barrier damage and oxidative injury than the unprocessed version while retaining the fluid-clearing effect. Processing changes the risk profile; it does not remove the toxic classification.
  • Combination changes the risk. Toxicity is not a fixed property of the herb. See the interactions section for what happened when it was studied together with licorice, the herb it is classically forbidden to combine with.

  Sources: PMID 41120103, DOI 10.1111/bph.70219 (British Journal of Pharmacology, 2026 — glycosphingolipids disrupt gut motility and fluid balance via TRPA1 activation in enterochromaffin cells); PMID 36426741, DOI 10.1002/ptr.7673 (Phytotherapy Research, 2024 — liver- and kidney-injured rats induced by Euphorbia pekinensis); PMID 41044610, PMC 12495871, DOI 10.1186/s13020-025-01224-9; PMID 39205630, DOI 10.1080/14786419.2024.2397554. Reference safety information, not a description of use.

• This herb is considered toxic.
  (while some Chinese herbs are toxic, it must be noted that many come prepared, or are combined, to mitigate their toxicity)

Herb-Drug Interactions

• No controlled clinical herb–drug interaction studies exist for Jing Da Ji. The best-characterised interaction is herb–herb: the classical prohibition on combining it with Gan Cao (licorice, Radix Glycyrrhizae), one of the Eighteen Incompatibilities and a pair our own incompatibility records hold.

  What modern work found when it tested that pair is genuinely mixed, and we report it as such. A 2025 study combined chemical profiling, rat toxicity assessment and a mouse model of liver-cancer ascites. Pairing the root with licorice raised the measured content of most of its chemical components; on the efficacy side, the combination reduced ascites volume, body weight and waist circumference more effectively than the root alone, with enhanced down-regulation of renal aquaporins offered as the mechanism. On the safety side, the same study found the root alone damaged intestinal tissue, and that the combination additionally produced slight damage to liver and spleen.

  Discrepancy noted: that result does not straightforwardly confirm or refute the classical prohibition — the pairing performed better on the ascites endpoint while broadening the pattern of organ damage. We present it as the current experimental picture rather than as vindication of either position, and the classical incompatibility stands as the operative rule for practitioners. Because glycyrrhizin from licorice is present in a very large number of herbal formulas, in some confectionery and in supplements, incidental co-exposure is a practical consideration as well as a classical one.

  Beyond that: given a violent purgative action and documented hepatorenal injury on repeated dosing, concurrent use with hepatotoxic or nephrotoxic medication, with diuretics, or with any drug whose absorption or electrolyte balance would be disturbed by profound fluid loss is a reasonable theoretical concern. (Precautionary reference context flagged for practitioner confirmation, not a demonstrated clinical interaction list.)

  Sources: our own incompatibility records; PMID 40286674, DOI 10.1016/j.jpba.2025.116914 (Journal of Pharmaceutical and Biomedical Analysis, 2025 — Euphorbiae Pekinensis Radix with Glycyrrhizae Radix for remission of ascites in hepatocellular carcinoma); PMID 36426741, DOI 10.1002/ptr.7673. Reference context, not clinical 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 Jing Da Ji (Euphorbia pekinensis)?

  Yes — an active phytochemical, pharmacological and toxicological literature, concentrated on the diterpenoids, on malignant ascites, and on the mechanism of the herb’s gut toxicity. There are no controlled human efficacy trials to report, and everything below is context rather than evidence of benefit. A 2025 comprehensive review counts 79 characterised compounds — principally diterpenoids, triterpenoids, tannins and phenols, plus 29 volatile constituents — and identifies the diterpenoids as the primary active class.

  • Mechanism of the purgative effect — the 2026 glycosphingolipid/TRPA1/serotonin work described in the toxicity section is the clearest account yet of how this root produces diarrhoea, and it identifies the responsible constituent class rather than inferring it.
  • Malignant ascites (animal) — the most active clinical-facing thread. Studies have compared processed against unprocessed Shi Zao Tang in ascites rats, mapped the contribution of the jujube component to reducing intestinal injury, and examined the root paired with licorice in a mouse liver-cancer ascites model. Gut microbiota, tryptophan and tyrosine metabolism, and aquaporin expression recur as the proposed mechanisms.
  • Oncology (preclinical) — a 2024 study reported that the herb sensitised colorectal cancer to PD-1 blockade in a model system by remodelling the tumour microenvironment, and new terpenoids with selective anti-hepatocellular-carcinoma activity in cell assays were reported in 2026. Laboratory findings about isolated chemistry, with no implication for herbal use.
  • Toxicology — hepatorenal injury from the total diterpenes has been characterised in rats, and detoxification through processing has been studied both for this species and comparatively across related toxic Euphorbia species.
  • Quality control — DNA barcoding combined with chromatographic fingerprinting has been developed to separate authentic material from counterfeits and adulterants, and quality-marker identification strategies have used this root as their worked example.

  Overall: substantial preclinical chemistry, a well-developed animal literature on ascites, an unusually clear toxicology, and no human clinical evidence base. Research context, not a therapeutic claim.

  Sources: PMID 39205630, DOI 10.1080/14786419.2024.2397554; PMID 41120103, DOI 10.1111/bph.70219; PMID 41044610, PMC 12495871, DOI 10.1186/s13020-025-01224-9; PMID 39084184, DOI 10.1016/j.phymed.2024.155895; PMID 40286674, DOI 10.1016/j.jpba.2025.116914; PMID 39368338, DOI 10.1016/j.phymed.2024.156107 (Phytomedicine, 2024 — sensitisation of colorectal cancer to PD-1 blockade); PMID 41643782 (Fitoterapia, 2026 — new terpenoids with anti-hepatocellular carcinoma activity); PMID 36426741, DOI 10.1002/ptr.7673; PMID 39109414, DOI 10.1002/bmc.5978. Research context, not a therapeutic claim.

Chinese Herb Notes

• Which “Da Ji” is this — and how is it different from the others?

  This is the toxic purgative Da Ji (大戟), used to drive out water and phlegm-fluid. Two closely-related toxic roots share the name: Jing Da Ji (京大戟, Radix Euphorbiae Pekinensis — Euphorbia pekinensis) and Hong Da Ji (红大戟, Radix Knoxiae — Knoxia valerianoides); both are harsh downward-draining (expel-water) agents historically used interchangeably as “Da Ji.” This is entirely different from the hemostatic thistle Da Ji (大蓟, Herba Cirsii Japonici) — a non-toxic, blood-cooling herb that only shares the romanised name.

  The three-way distinction, stated plainly:

  • Jing Da Ji (京大戟) — Euphorbia pekinensis, family Euphorbiaceae. Toxic harsh expellant. This is the classical 大戟 of the formula literature and the herb this page describes.
  • Hong Da Ji (红大戟) — Knoxia valerianoides, family Rubiaceae. A botanically unrelated toxic root that entered the trade as a substitute under the same name, and which we hold as its own separate record. It is not a synonym for this herb.
  • Da Ji (大蓟) — Cirsium japonicum, the Japanese thistle. Non-toxic, cools blood and stops bleeding. Shares nothing with the two roots above except a romanisation collision.

  Which formulas on this site contain Jing Da Ji?

  Two: Shi Zao Tang (Ten Jujube Decoction) and Zhou Che Wan (Vessel and Vehicle Pill) — both severe, excess-pattern water-expelling formulas, presented here as historical and reference entries. In Shi Zao Tang it appears alongside Gan Sui and Yuan Hua, buffered by jujube; experimental work has since shown that the jujube component measurably reduces the intestinal injury caused by the three water-expelling members, giving a modern reading of a compositional choice made two millennia ago.

  Record flags (identity fields left unchanged, raised for owner review). Three naming artefacts remain in our own data around this herb. First, this record’s alternate-names field lists Hong Da Ji as a “related substitute,” while Hong Da Ji is properly a distinct herb with its own entry — the two should not read as one substance. Second, the thistle Cirsium record carries “Jing Da Ji” among its alternate names, which is incorrect: the thistle is 大蓟 and has no connection to this Euphorbia. Third, our incompatibility records hold both Gan Cao ↔ Jing Da Ji (correct, and the classical pair) and Gan Cao ↔ Da Ji (Cirsium), which is a residual artefact of the same name collision. We have not altered any of them.

  Sources: our own herb, incompatibility and formula records; standard materia medica consensus for the harsh expel-water category, cross-referenced against multiple online sources; PMID 39205630, DOI 10.1080/14786419.2024.2397554; PMID 39084184, DOI 10.1016/j.phymed.2024.155895 (Phytomedicine, 2024 — jujube with the water-expelling members of Shi Zao Tang reduced intestinal injury). Reference documentation, not usage guidance.

This herb is incompatible with:

• Gan Cao (Radix Glycyrrhizae)

This herb is considered toxic