Traditionally used for
- Cough & breathing
- Digestion
- Pain & joints
- Skin
Cautions & contraindications
- Pregnancy
- Breastfeeding
- Young children
- Heart conditions
- Toxic — professional use only
☯ TCM Properties
Induces Vomiting to Expel Phlegm; Expels Parasites; Relieves Itching and Treats Sores
Traditional Chinese Uses
Li Lu (veratrum root and rhizome, false hellebore) is an extremely toxic herb with a powerful emetic action used only in emergencies for acute Phlegm obstruction or toxic ingestion. Internally, it also expels stubborn Wind-Phlegm from the channels in severe bi syndrome. It is considered incompatible with many common herbs and must never be used without strict professional supervision and careful dose measurement. Its extreme toxicity means it is one of the least commonly prescribed herbs in modern Chinese clinical practice.
Relationships
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Botanical Description
Veratrum nigrum, the black false hellebore, is a stout perennial herb of the Melanthiaceae family growing 60 to 100 cm tall from a short erect rhizome bearing many thick fleshy roots. The basal leaves are large, broadly elliptic, 20 to 35 cm long, with strongly parallel longitudinal veins, prominently plicate, and clasping at the base; cauline leaves become progressively smaller upward. The inflorescence is a large terminal panicle, 20 to 60 cm long, of numerous small flowers with six dark purplish-black to maroon tepals about 6 to 8 mm long, the lateral branches densely flowered. The fruit is a three-lobed septicidal capsule containing winged seeds. It is native to grasslands and open woodlands across temperate Eurasia. All parts contain extremely toxic steroidal alkaloids including jervine and protoveratrines.
Active Constituents
Cyclopamine (11-deoxojervine)
C-nor-D-homo steroidal alkaloid (Veratrum-type)Concentration: a minor alkaloid by mass but pharmacologically dominant; it is detectable in human blood and breast milk after Veratrum ingestion
A potent antagonist of Smoothened in the Hedgehog signalling pathway. This is the mechanism of its severe teratogenicity: it is the compound responsible for cyclopia and craniofacial malformation in lambs born to ewes grazing Veratrum, and there is no reason to think human embryos are protected. Veratrum nigrum must not be given in pregnancy or to women who may become pregnant.
Jervine
C-nor-D-homo steroidal alkaloid (Veratrum-type)Concentration: isolated from Veratrum nigrum as well as V. album, V. viride and V. californicum
A second Hedgehog pathway inhibitor and teratogen with the same mechanism as cyclopamine. It has attracted separate interest as an antifungal, anti-inflammatory and antitumour lead, but that interest is in the isolated compound, not in the crude drug.
Veratramine
C-nor-D-homo steroidal alkaloid (Veratrum-type)Concentration: detected in patient blood and, in one lactating patient, in breast milk after Veratrum poisoning
Contributes to the neurological features of Veratrum poisoning. Its documented passage into human breast milk means the herb is contraindicated in lactation as well as pregnancy.
Veratridine
Veratrum ester alkaloid (cevanine-type ester alkaloid)Concentration: content in the crude drug rises measurably when Veratrum nigrum is combined with Radix Paeoniae Alba, tracking the increase in acute toxicity
Binds site 2 of the voltage-gated sodium channel and holds it open, producing persistent depolarisation. This underlies the emetic action exploited in classical practice and, at only slightly higher exposure, the bradycardia, hypotension, paraesthesia and vomiting of Veratrum poisoning. It is directly cytotoxic to SH-SY5Y neuronal cells, an effect reduced by increasing concentrations of paeoniflorin.
Resveratrol
StilbenoidConcentration: one of the stilbene fraction among roughly 137 compounds isolated from the root, rhizome and whole plant
The plant's non-alkaloid constituents include stilbenes, flavonoids, organic acids and dipeptides, but the steroidal alkaloids are both the most abundant and the determinants of the drug's activity and its toxicity. The stilbene fraction has no bearing on safe dosing.
⚠ Drug Interactions
Antihypertensives, beta-blockers and calcium channel blockers (e.g. amlodipine, metoprolol, verapamil)
Veratrum ester alkaloids hold voltage-gated sodium channels open in cardiac and vagal afferent fibres, triggering the Bezold-Jarisch reflex. In a documented cluster of eight patients who ate Veratrum parviflorum mistaking it for ramps, nausea, vomiting, hypotension, bradycardia, abdominal pain, light-headedness, blurred vision and arm paraesthesia appeared within one to four hours, and the haemodynamically unstable required atropine and vasopressors (Seale et al., Clinical Toxicology 2022). Veratrum alkaloids were historically used as antihypertensives and abandoned precisely because the margin between hypotensive effect and toxicity is too narrow.
Clinical note: Do not combine. Veratrum nigrum is a narrow-margin cardiotoxic herb, not a hypotensive adjunct. Any patient on cardiovascular medication who has taken it and reports vomiting with dizziness needs emergency assessment for bradycardia and hypotension.
Cardiac glycosides and antiarrhythmics (e.g. digoxin, amiodarone, class I antiarrhythmics)
Sodium channel modification by veratrum ester alkaloids produces bradycardia and conduction disturbance in its own right, and the reported human poisoning syndrome is dominated by bradycardia. Adding a drug that independently slows conduction or increases vagal tone compounds the same endpoint. The combination has not been studied deliberately in humans for obvious reasons.
Clinical note: Treat as an absolute contraindication in patients on digoxin or any antiarrhythmic, and in anyone with pre-existing bradycardia, sick sinus syndrome or AV block.
Panax ginseng and the other eighteen-incompatibility partners (ren shen, sha shen, dan shen, xuan shen, ku shen, xi xin, shao yao)
These pairings are the classical shi ba fan (eighteen incompatibilities) prohibitions, and modern work supports them. Combining Veratrum nigrum with Radix Paeoniae Alba raised acute toxicity in rodents whenever the Veratrum dose equalled or exceeded that of the paeony, and UPLC-TOF-MS showed the content of specific veratrum alkaloids rose in parallel, correlating strongly with the toxicity (Zhang et al., 2014). Separately, Veratrum nigrum blunted the oestrogenic effect of Panax ginseng in immature mice, attenuating the rise in serum oestradiol and the upregulation of ERalpha and ERbeta (Xu et al., 2016), and weakened ginseng's anti-proliferative and anti-metastatic activity in colorectal models (Kee et al., 2018).
Clinical note: Do not prescribe Li Lu in the same formula, or the same day, as any of the ginsengs, xi xin or shao yao. Check every co-prescribed proprietary formula for hidden ginseng content.
Hedgehog pathway inhibitors (e.g. vismodegib, sonidegib)
Cyclopamine and jervine, both present in Veratrum nigrum, are the archetypal natural Smoothened antagonists and act on the same target as vismodegib and sonidegib. Both prescription drugs already carry absolute pregnancy contraindications on teratogenic grounds; adding a plant containing the compound that defined the teratogenic phenotype is indefensible. No formal interaction study exists, and none is needed to justify the prohibition.
Clinical note: Absolute contraindication. More broadly, Veratrum nigrum must never be given in pregnancy, to anyone who might become pregnant, or during lactation, since cyclopamine and veratramine have been detected in human breast milk.
Any concurrently swallowed oral medication
The classical internal indication for Li Lu is to induce vomiting in order to expel phlegm; emesis is the intended effect, not an adverse one. Any oral drug taken within the same window is liable to be expelled before absorption, which matters most for anticonvulsants, antiretrovirals, immunosuppressants, anticoagulants and oral contraceptives.
Clinical note: In practice this is one more reason the internal, emetic use is essentially obsolete and most modern practice restricts Li Lu to external application for parasites and itching. Classical internal doses are sub-gram powder doses, and the herb should not be decocted freely or self-administered.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| not recommended | Not established for dispensing — see note | — | — | — | No Chinese Pharmacopoeia 2025 monograph found for this drug, so no pharmacopoeial dose is given here. Li Lu (藜芦, *Veratrum nigrum*) is NOT in the current Chinese Pharmacopoeia. It is a drastic emetic and a potent cardiotoxin: the veratrum alkaloids cause protracted vomiting, bradycardia, hypotension and cardiac conduction block, and the margin between an emetic and a toxic dose is very narrow. Classical texts give a dose in the region of 0.3–0.9 g, but that is a historical figure and not a pharmacopoeial one. By the eighteen incompatibilities it is not combined with the ginsengs (Ren Shen, Sha Shen, Dan Shen, Xuan Shen, Ku Shen), Xi Xin or the peonies. Contraindicated in pregnancy and in the weak. The previous value was generic filler generated from tcm_category and was cleared; it has not been replaced with an estimate. |
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
1
0 verified · 1 unverified
In vitro / animal
3
0 verified · 3 unverified
Show 3 studies
- The Correlation between Chemical Composition, as Determined by UPLC-TOF-MS, and Acute Toxicity of Veratrum nigrum L. and Radix paeoniae alba
- Effect of the Interaction of Veratrum Nigrum with Panax Ginseng on Estrogenic Activity In Vivo and In Vitro
- Pharmacological effect of prohibited combination pair Panax ginseng and Veratrum nigrum on colorectal metastasis in vitro and in vivo
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
Veratrum parviflorum poisoning: identification of steroidal alkaloids in patient blood and breast milk
Eight patients in Georgia and North Carolina were poisoned in spring 2020-2021 after foraging Veratrum parviflorum in mistake for ramps. Symptoms began within one to four hours: nausea, vomiting, hypotension, bradycardia, abdominal pain, light-headedness, blurred vision and arm paraesthesia; unstable patients needed atropine and vasopressors. Plant extract contained cyclopamine, veratramine, jervine and muldamine; cyclopamine and jervine were found in patient blood, and cyclopamine and veratramine in the breast milk of a lactating patient, the first identification of Veratrum alkaloids in human milk. The species is North American rather than Veratrum nigrum, but the alkaloid class and the clinical syndrome are the same, and this is the clearest modern documentation of the toxidrome.
The Correlation between Chemical Composition, as Determined by UPLC-TOF-MS, and Acute Toxicity of Veratrum nigrum L. and Radix paeoniae alba
Acute toxicity rose when the dose of Veratrum nigrum equalled or exceeded that of Radix Paeoniae Alba in combination. UPLC-TOF-MS showed that although the amount of Veratrum was held constant, the measured content of several veratrum alkaloids changed markedly and correlated strongly with toxicity, indicating that the combination alters extraction or stability of the alkaloids rather than merely adding two effects. In SH-SY5Y cells the cytotoxicity of veratridine fell as paeoniflorin concentration rose. The work gives a chemical basis for the classical prohibition on pairing Li Lu with shao yao.
Effect of the Interaction of Veratrum Nigrum with Panax Ginseng on Estrogenic Activity In Vivo and In Vitro
Veratrum nigrum reduced the oestrogenic efficacy of Panax ginseng in immature mice, blunting the promotion of uterine and vaginal development, attenuating the rise in serum oestradiol and reducing upregulation of ERalpha and ERbeta. The paper provides systematic evidence that the classical incompatibility is a real pharmacodynamic antagonism rather than a purely doctrinal prohibition. A corrigendum correcting a reference-list error was published in 2017.
Pharmacological effect of prohibited combination pair Panax ginseng and Veratrum nigrum on colorectal metastasis in vitro and in vivo
The combined Panax ginseng plus Veratrum nigrum extract showed weaker anti-proliferative and anti-metastatic activity than ginseng alone, in both cell and animal colorectal metastasis models. Veratrum nigrum attenuated the anti-metastatic effect of ginseng rather than adding to it, a second independent line of evidence that the pairing degrades the intended action of the partner herb.
⚠ Safety & Contraindications
- Pregnancy
- Breastfeeding
- Young children
- Heart conditions
- Toxic — professional use only
Contraindications
Contraindicated in pregnancy, in cardiac disease, in the weak or depleted, and in children.
Safety Warnings
- Used almost entirely as an emetic and externally; internal use is rare and minute.
- Incompatible with Ren Shen, Sha Shen, Dan Shen, Xuan Shen, Xi Xin and Shao Yao under the classical eighteen incompatibilities.
- Cyclopamine is a potent teratogen.
⚠ Rule-Based Cautions
These entries come from the deterministic rule tables that gate Verscienta's formula tools — classical pair prohibitions, pregnancy and lactation contraindications, and dose ceilings.
Incompatibilities (十八反 / 十九畏)
- 十八反: Li Lu × Ren Shen — avoid combining with Ren Shen / Ginseng / Panax ginseng
- 十八反: Li Lu × Dan Shen — avoid combining with Dan Shen / Salvia miltiorrhiza
- 十八反: Li Lu × Xuan Shen — avoid combining with Xuan Shen / Scrophularia
- 十八反: Li Lu × Sha Shen — avoid combining with Sha Shen / Adenophora / Glehnia
- 十八反: Li Lu × Xi Xin — avoid combining with Xi Xin / Asarum
- 十八反: Li Lu × Shao Yao — avoid combining with Bai Shao / Chi Shao / Paeonia
- 十八反: Li Lu × Ku Shen — avoid combining with Ku Shen / Sophora flavescens
⚠ Toxicity Information
Intense vomiting, then bradycardia and profound hypotension from the Bezold–Jarisch reflex, with cardiac conduction disturbance. Poisonings, including fatalities, follow small overdoses.
Historical Texts
Shen Nong Ben Cao Jing
Han dynasty (compiled by the 2nd century CE)Ru Men Shi Qin
Jin dynasty (Zhang Congzheng, 1228)References
- Zhao X, Li S, Xiang Z, et al.. Veratrum nigrum L.: A comprehensive review of ethnopharmacology, phytochemistry, pharmacology, pharmacokinetics and metabolism, toxicity, and incompatibility . Journal of Ethnopharmacology (2024) [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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