Lang Du

Chinese Herb Actions

Chinese Herb Contraindications & Cautions

• Why is Lang Du restricted, and who should avoid it?

  Lang Du is documented across materia medica sources as contraindicated in pregnancy and in weak or deficient patients, and it is classically counted among the substances traditionally avoided in combination with certain other medicinals — together the reasons it is treated strictly as a professionally-supervised substance rather than a general-use herb. These are recorded here as public-safety reference facts explaining the restriction, not as usage or preparation guidance.

  • Pregnancy — consistently listed as contraindicated across materia medica sources, consistent with its classification as a harsh, markedly toxic, strongly irritant substance.
  • Weak or deficient patients — contraindicated in patients who are constitutionally weak, debilitated, or otherwise unable to tolerate a harsh, draining, irritant substance; also flagged against gastric ulceration in some sources.
  • Classical incompatibility — Lang Du is named in the classical Shi Jiu Wei (十九畹, “Nineteen Mutual Restraints”) list, a companion enumeration to the better-known Eighteen Incompatibilities: the traditional mnemonic records that “Lang Du fears Mi Tuo Seng” (狼毒画密限僧, láng dú wèi mì tuó séng), pairing it with Mi Tuo Seng (Lithargyrum / litharge, lead oxide) as a combination classically avoided.

  Source: classical materia medica compilations recording the Shi Jiu Wei (Nineteen Mutual Restraints) enumeration; standard TCM materia medica consensus on contraindications for toxic substances. Reference only, not usage guidance; a qualified practitioner determines appropriateness case by case.

Chinese Herb Toxicity & Overdose

• Lang Du is classified as a “greatly toxic” (大毒) substance in Chinese materia medica, and its toxicity is attributed to strongly irritant diterpenoid compounds concentrated in the root. Across its recognized botanical sources, these include tigliane/abietane/casbane-type diterpenoids and related esters in Euphorbia fischeriana/E. ebracteolata, and daphnane-type diterpenoids (e.g. gnidimacrin, the stelleralide series) in Stellera chamaejasme. Diterpenoid esters of these general classes are well documented in the phytochemistry literature as potent irritants to skin and mucous membranes, which is consistent with why the root is handled as a strongly irritant, toxic substance in both its historical topical and (much more cautiously) internal traditional uses.

  A 2021 systematic review of Euphorbia fischeriana traditional use, phytochemistry, pharmacology and toxicology explicitly concludes that, as a poisonous traditional medicine, existing toxicity studies remain insufficient and that particular attention should be paid to its handling and use — underscoring why the substance is reserved for professional supervision rather than general use.

  Source: PubMed 33819505 (Euphorbia fischeriana: traditional uses, phytochemistry, pharmacology and toxicology review, Journal of Ethnopharmacology 2021; DOI 10.1016/j.jep.2021.114095); PubMed 30179119 (Stellera chamaejasme chemistry/pharmacology review, noting diterpenoids as the principal bioactive/toxic constituent class); PubMed 37419377 (yuexiandajisu diterpenoid chemistry of Euphorbia ebracteolata “Langdu” roots). Toxicology reference, not a safety guarantee, and not usage or dosing guidance.

Herb-Drug Interactions

• No dedicated modern clinical herb–drug interaction studies for Lang Du are established. Given its documented diterpenoid-driven irritant and cytotoxic pharmacology (see research, below), reference sources would reasonably flag added caution around concurrent use with other agents that stress the liver, kidneys, or gastrointestinal mucosa, and around chemotherapeutic agents given overlapping cytotoxic mechanisms explored in preclinical anti-tumor research. This is precautionary, drawn from the toxicological/pharmacological profile rather than a demonstrated clinical interaction, and is not usage guidance. (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 Lang Du (Euphorbia fischeriana / E. ebracteolata / Stellera chamaejasme)?

  Yes — substantial modern phytochemistry and preclinical pharmacology research exists across its botanical sources, though the reviewing literature itself flags toxicology and human-clinical study as underdeveloped. A 2021 review catalogued 241 chemical constituents from Euphorbia fischeriana roots alone, spanning diterpenoids, triterpenoids, meroterpenoids, acetophenones, flavonoids, coumarins, steroids, phenolic acids and tannins, with documented antitumor, antibacterial, anti-inflammatory, antiviral and anti-leukemic bioactivities reported in laboratory and animal studies.

  • Euphorbia fischeriana chemistry and pharmacology — the 2021 Journal of Ethnopharmacology review is the most comprehensive synthesis of traditional uses, phytochemistry, pharmacology and toxicology for this botanical source, and explicitly identifies diterpenoids as warranting further in-depth research; it also states plainly that toxicity studies remain insufficient for a substance this poisonous.
  • Stellera chamaejasme chemistry and pharmacology — a parallel 2018 review of the Thymelaeaceae source catalogs flavonoids, coumarins, lignans and diterpenoids, identifying diterpenoids as the constituent class most consistently linked to antitumor activity, alongside reported antiviral, antibacterial, anticonvulsant, insecticidal, anti-inflammatory and immune-modulating effects — all laboratory/animal-model findings, not clinical evidence.
  • Yuexiandajisu diterpenoids (Euphorbia ebracteolata) — a 2023 Phytochemistry review focused specifically on a family of seven diterpenoid compounds isolated from E. ebracteolata “Langdu” roots (casbane-, isopimarane-, abietane- and rosane-type structures), several of which show marked anticancer activity in cell-line studies, alongside a phytotoxic compound in the same series — preclinical chemistry and cell-based findings, not clinical evidence.

  Across all three sources, the research base is preclinical (cell-line and animal-model), and each cited review separately notes that formal toxicology and clinical study of these toxic substances remain limited relative to the volume of phytochemistry and cytotoxicity work.

  Sources: PMID 33819505, DOI 10.1016/j.jep.2021.114095 (Euphorbia fischeriana review, Journal of Ethnopharmacology, 2021); PMID 30179119, DOI 10.2174/1381612824666180903110802 (Stellera chamaejasme chemistry/pharmacology review, Current Pharmaceutical Design, 2018); PMID 37419377, DOI 10.1016/j.phytochem.2023.113784 (yuexiandajisu diterpenoids of Euphorbia ebracteolata “Langdu” roots, Phytochemistry, 2023). Research context, not a therapeutic claim.

Chinese Herb Notes

• What plant does Lang Du come from, and why do sources disagree on the botanical name?

  “Lang Du” is a vernacular TCM name applied to the toxic roots of at least two botanically unrelated plant families, which is why Latin names for it vary across sources. Standard references recognize Euphorbia fischeriana Steud. and Euphorbia ebracteolata Hayata (family Euphorbiaceae, spurge family — sources more typical of northern China) and Stellera chamaejasme L. (family Thymelaeaceae, daphne family — a source more typical of western/high-altitude China, sometimes distinguished in Chinese as 璃香狼毒, Ruì xiāng láng dú) as parallel accepted origins for the same traditional name, all sharing a similarly toxic, irritant root used the same way.

  • Euphorbiaceae sources (E. fischeriana, E. ebracteolata) — the sources reflected in the site’s current Sacred Lotus Latin name, “Radix Euphorbiae Fischerianae.”
  • Thymelaeaceae source (Stellera chamaejasme) — a botanically distinct plant carrying the same TCM name and toxic-root use; the more composite Latin rendering “Radix Euphorbiae Ebracteolatae seu Stellerae” explicitly names both plant-family origins together.

  Note: the site’s Sacred Lotus currently records only the Euphorbiaceae Latin name (Radix Euphorbiae Fischerianae), while the broader literature and the composite Latin name also recognize the Thymelaeaceae source (Stellera chamaejasme) as an accepted parallel origin for the same TCM substance. We treat these as the same traditionally-used substance under one vernacular name rather than a naming error, and leave Sacred Lotus sources & references field unchanged pending owner review.

  Chemically, the shared toxic/irritant principle across these botanical sources is a family of diterpenoid compounds: tigliane-, abietane-, casbane-, isopimarane- and rosane-type diterpenoids (including a distinct group termed “yuexiandajisu” A–F) have been isolated from the Euphorbiaceae roots, while daphnane-type diterpenoids (including gnidimacrin and the stelleralide series) dominate in Stellera chamaejasme, alongside flavonoids, coumarins, lignans and biflavanones. Phorbol- and daphnane-ester–type diterpenoids of this general class are well established in the broader phytochemistry literature as potent skin and mucous-membrane irritants, consistent with Lang Du’s classification as a harsh, toxic substance.

  Within the materia medica, Lang Du is often discussed alongside other toxic Euphorbiaceae-family purgative/phlegm-fluid herbs such as Da Ji, Gan Sui and Yuan Hua because of shared botanical family and toxicity profile, but it is traditionally distinguished from that group by its emphasis on breaking up scrofula/masses and its topical parasiticide use, rather than primarily draining generalized edema or ascites.

  Source: PubMed 33819505 (Euphorbia fischeriana review); PubMed 30179119 (Stellera chamaejasme chemistry/pharmacology review); PubMed 37419377 (yuexiandajisu diterpenoids of Euphorbia ebracteolata “Langdu” roots, review); materia medica consensus on category placement.