Traditionally used for
- Urinary & fluids
- Heart & circulation
- Skin
Cautions & contraindications
- Pregnancy
- Bleeding disorders
- Kidney conditions
- Toxic — professional use only
☯ TCM Properties
Attacks toxin and e rodes sores; Invigorates the Blood, d ispels Blood Stasis and disperses clumps
Traditional Chinese Uses
Ban Mao is the dried body of blister beetles of the genus Mylabris (chiefly Mylabris phalerata), the Chinese analogue of cantharides. Pungent and cold and classed with external, toxin-attacking agents, it attacks toxin and erodes sores, and invigorates the Blood to break up Blood stasis and disperse hard clumps. Externally it has been used as a caustic/vesicant on stubborn tinea, warts and malignant sores; internally, in minute doses, it was given for masses and scrofula, and, in modern practice, as a source of cantharidin in anti-tumor formulas.
Safety is critical: Ban Mao is highly toxic. Its active constituent, cantharidin, is a potent vesicant with a very narrow margin between effective and lethal dose, causing severe gastrointestinal, urinary (hemorrhagic cystitis), cardiac and renal toxicity. It is strictly contraindicated in pregnancy and must only be used by qualified practitioners; it is never for self-administration.
Relationships
Full-screen graph →Click a node for details · double-click to expand it · Ctrl/⌘ + scroll or two fingers to zoom and pan.
Botanical Description
Ban Mao is not a plant but the dried whole body of blister beetles in the genus Mylabris, principally Mylabris phalerata and M. cichorii (Coleoptera: Meloidae), collected in central and southern China during the warm season. These beetles are stout, elongate insects approximately one and a half to three centimeters long, with soft flexible elytra typically marked by alternating transverse bands of orange-yellow and black, a small head bent downward, and prominent thread-like antennae. The insects are gathered in early morning when sluggish from cool temperatures, killed by steaming or boiling, and dried whole for medicinal use. The body contains high concentrations of cantharidin, a powerful blistering vesicant historically extracted from related Old World blister beetles and notorious for severe systemic toxicity.
Active Constituents
Cantharidin
Bicyclic monoterpenoid anhydride (terpenoid vesicant)Concentration: Reported around 0.16% of the whole dried beetle in one body-part survey of Mylabris phalerata (head 0.050%, feet 0.042%, elytra 0.044%, hindwings 0.024%); published values across Mylabris species and seasons range far more widely, up to about 1%
Cantharidin is the sole reason this drug exists and the sole reason it kills. It is a potent, selective inhibitor of protein phosphatase 2A (and PP1), which underlies both its antiproliferative action and its organ toxicity. On skin and mucosa it is a severe vesicant, splitting the epidermis at the level of the desmosome and raising blisters within hours. Swallowed, it produces burning of the mouth and pharynx, dysphagia, haemorrhagic gastroenteritis with haematemesis and rectal bleeding, then haemorrhagic cystitis, dysuria and haematuria, and acute tubular necrosis with acute renal failure; cardiomyocyte necrosis has been found at autopsy. Reported human lethal doses cluster around 10 mg of cantharidin in adults, with fatalities documented at that dose and survival reported after 50 mg, so the lethal quantity is on the order of a few beetles. Against the pharmacopoeial single oral dose of processed Mylabris (0.03 to 0.06 g of beetle, delivering roughly 0.05 to 0.6 mg of cantharidin at the concentrations above), that leaves a margin of only some tens of doses, and no useful margin at all if the material is poorly processed or the species substituted.
Cantharimide and its N-substituted derivatives
Cantharidin-derived imidesConcentration: Minor constituents isolated from Mylabris phalerata; not quantified in the source reports
A small group of imide analogues of cantharidin isolated from the beetle alongside the parent anhydride. They are of chemical interest because the semisynthetic imide and demethylated analogues (norcantharidin, disodium cantharidinate) were developed specifically to retain the antitumour phosphatase inhibition while reducing the urinary tract and renal toxicity of cantharidin itself.
Cantharidin-related terpenoid analogues
Monoterpenoid anhydrides and related oxygenated derivativesConcentration: Trace; three novel members characterised from Mylabris phalerata by Nakatani and colleagues
Structurally related minor terpenoids reported from the same beetle. They are not the drug's therapeutic principle and are not present at concentrations that alter its toxicity, but they matter for chemical fingerprinting when authenticating Mylabris against other blister beetles.
Fatty acids (oleic, linoleic, palmitic and stearic acids)
Long-chain fatty acidsConcentration: Bulk lipid fraction of the beetle body; not standardised
Structural lipids of the insect body with no established pharmacological role in this drug. They are relevant only insofar as cantharidin is lipid-soluble and partitions into fatty vehicles, which is why oil-based or alcohol-based topical preparations of Ban Mao produce more vesication than aqueous ones.
⚠ Drug Interactions
Nephrotoxic drugs (aminoglycosides, cisplatin, amphotericin B, NSAIDs, ciclosporin, tenofovir)
Cantharidin is excreted renally and concentrates in tubular epithelium, where it causes acute tubular necrosis and glomerular damage. Transcriptomic work in mice exposed to cantharidin showed rising serum creatinine and uric acid, oxidative stress and clear pathological injury to glomerular and tubular epithelial cells. Renal dysfunction is the commonest serious feature of human cantharidin poisoning. Any co-administered nephrotoxin adds to that injury on the same target tissue, and volume depletion from the drug's own haemorrhagic gastroenteritis compounds it further.
Clinical note: Do not use Ban Mao internally in anyone with existing renal impairment or on a nephrotoxic drug. If internal use is being considered at all, baseline and serial creatinine, urinalysis for haematuria, and maintained hydration are minimum requirements. Haematuria or dysuria means stop immediately.
Anticoagulants and antiplatelet agents (warfarin, apixaban, heparin, aspirin, clopidogrel)
Cantharidin blisters mucosal surfaces the way it blisters skin. Documented human poisoning features include haematemesis, occult and frank rectal bleeding, gross haematuria, vaginal bleeding and low-grade disseminated intravascular coagulation. Adding a drug that impairs haemostasis converts a vesicating mucosal injury into an uncontrolled bleed, and there is no antidote to cantharidin to fall back on.
Clinical note: Treat internal Ban Mao as contraindicated in any anticoagulated or antiplatelet-treated patient. Even topical use over large or broken skin areas warrants caution, since cantharidin is absorbed through damaged skin.
Urinary tract irritants and drugs causing haemorrhagic cystitis (cyclophosphamide, ifosfamide, ketamine)
Cantharidin reliably produces haemorrhagic cystitis in humans and is used experimentally to model it in rats. Oxazaphosphorine chemotherapy causes the same lesion through acrolein. The two mechanisms are different but the target epithelium is identical, so concurrent exposure is expected to be additive. This matters in practice because cantharidin derivatives are given adjunctively with chemotherapy in China.
Clinical note: Avoid raw Ban Mao entirely in patients receiving cyclophosphamide or ifosfamide. If a regulated cantharidin derivative such as disodium cantharidinate is being used alongside chemotherapy, that is a hospital decision with monitoring, not a dispensary one.
Lytta vesicatoria (Spanish fly) and other cantharidin-containing blister beetles sold as aphrodisiacs
Cantharidin is not unique to Mylabris. Lytta vesicatoria (Spanish fly), Epicauta species and several Oedemeridae contain the same molecule, and street aphrodisiac preparations sold under those names have caused the identical syndrome of oral burning, haemorrhagic gastroenteritis, priapism and renal failure. Because the toxin is chemically identical, a patient taking Ban Mao and a Spanish fly preparation is simply taking a larger cantharidin dose than either label suggests, and cantharidin content varies unpredictably between beetle species and body parts. Poisoning has also followed accidental ingestion of blister beetles contaminating food or forage.
Clinical note: Ask directly about aphrodisiac products and imported insect preparations before dispensing anything containing Mylabris. Confirm the material is authenticated Mylabris phalerata or M. cichorii and correctly processed; unauthenticated 'blister beetle' material should not be used.
Pregnancy and abortifacient use (any concurrent uterotonic)
Ban Mao has a folk reputation as an abortifacient and this is one of the recurring routes to fatal poisoning. Cheng and colleagues reported a death in Hong Kong from cantharides taken from Mylabris phalerata specifically for that purpose. Cantharidin has no selective uterine action; the apparent effect is the systemic toxicity of a vesicant that damages the gut, bladder, kidney and heart, and the dose needed to provoke abortion overlaps the dose that kills the woman.
Clinical note: Absolutely contraindicated in pregnancy by any route, and this needs to be stated to patients rather than left implicit. A patient presenting with cantharidin poisoning after attempted self-abortion needs supportive care with attention to renal function and haemorrhage; there is no antidote.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| powder | 0.03–0.06 g | — | — | — | ChP 2025 (yaobw.cn mirror; cross-validated against db.ouryao.com). 炮制后多入丸散用 — processed, in pills or powder. 本品有大毒，内服慎用；孕妇禁用 — SEVERELY TOXIC (大毒); internal use only with great caution; contraindicated in pregnancy. Cantharidin is a potent vesicant and nephrotoxin; the lethal dose is on the order of tens of milligrams. Replaces a generic filler value generated from tcm_category, which had been cleared to blank. |
| topical | Appropriate amount | — | — | — | ChP 2025 (yaobw.cn mirror; cross-validated against db.ouryao.com). 外用适量，研末或浸酒醋，或制油膏涂敷患处，不宜大面积用 — powdered, or steeped in wine or vinegar, or as an ointment; NOT to be applied over a large area (cantharidin is absorbed through skin). |
Evidence Tier
Strong evidence · 6 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
1
1 verified · 0 unverified
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
3
1 verified · 2 unverified
In vitro / animal
1
1 verified · 0 unverified
Other / unclassified
1
1 verified · 0 unverified
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Cantharides poisoning: A retrospective analysis from 1996 to 2016 in China
Retrospective analysis of 91 reported cases of cantharides poisoning in China over twenty years, with a case fatality rate of 18.68%. Poisoning followed both medicinal use and accidental or deliberate ingestion. Autopsy findings in fatal cases included cardiomyocyte necrosis and neuronal apoptosis, alongside the expected gastrointestinal and renal injury. The authors attribute the poisonings to the very narrow gap between the therapeutic and toxic dose of cantharidin.
A Fatality Due to the Use of Cantharides from Mylabris Phalerata as an Abortifacient
Report of a fatal poisoning in which cantharides prepared from Mylabris phalerata was taken as an abortifacient. This is one of the few published fatalities tied to the named species rather than to blister beetles generally, and it documents the route by which many of the severe cases arise.
Acute kidney injury by cantharidin poisoning following a silly bet on an ugly beetle
A previously healthy adult developed acute kidney injury after swallowing a single blister beetle. The case illustrates how small an exposure to cantharidin is needed to produce clinically significant renal failure, and that the injury pattern is acute tubular necrosis.
Transcriptomic profiling and differential analysis reveal the renal toxicity mechanisms of mice under cantharidin exposure
Mice given cantharidin showed raised serum creatinine and uric acid, increased renal oxidative stress markers, and clear histopathological damage to glomerular and tubular epithelial cells. Transcriptomic profiling implicated inflammatory and oxidative stress pathways in the tubular injury, giving a mechanistic account of the acute renal failure seen in human poisoning.
Efficacy and safety of sodium cantharidinate and vitamin B6 injection for the treatment of digestive system neoplasms: a meta-analysis of randomized controlled trials
Meta-analysis of randomised trials of sodium cantharidinate with vitamin B6 injection added to conventional therapy in gastrointestinal cancers, reporting improved response rates and quality-of-life measures. Note that this evidence concerns a purified, dose-controlled parenteral cantharidin salt given in hospital, not raw Mylabris taken by mouth; the trials are almost all Chinese-language and single-centre, so the finding should be read as promising rather than definitive.
Disodium Cantharidinate and Vitamin B6 Injection Adjunct with Platinum-Based Chemotherapy for the Treatment of Advanced Non-Small-Cell Lung Cancer: A Meta-Analysis
Meta-analysis of randomised trials adding disodium cantharidinate with vitamin B6 injection to platinum-based chemotherapy in advanced non-small-cell lung cancer, reporting better response rates and fewer haematological adverse events than chemotherapy alone. The same caveats apply as for the digestive-cancer meta-analysis: the product is a standardised injectable cantharidin salt used under oncological supervision, and the included trials are of modest methodological quality.
⚠ Safety & Contraindications
- Pregnancy
- Bleeding disorders
- Kidney conditions
- Toxic — professional use only
Contraindications
Contraindicated in pregnancy and in any renal disease. Not for use in the weak or depleted.
Safety Warnings
- Chiefly an external medicine; internal use is rare, minute, and only within a formal clinical setting.
- Handle with gloves — cantharidin blisters skin on contact.
- Renal function should be monitored where any internal use is contemplated.
⚠ Toxicity Information
Burning of the mouth and throat, vomiting, haematemesis, severe abdominal pain, haematuria and acute renal failure. Skin contact blisters. Death from renal failure or cardiovascular collapse is documented at low doses.
Historical Texts
Shen Nong Ben Cao Jing
Han dynastyBen Cao Gang Mu
Ming dynastyReferences
- Guo Huan; Ren Wenshuo; Guo Meizhu; Wu Xia; Guo Qiang. A Comprehensive Review on Ethnopharmacology, Phytochemistry of Mylabris, and Pharmacology of Cantharidin . Chemistry & Biodiversity (2025) [DOI]
- Li Y M; Casida J E. Cantharidin-binding protein: identification as protein phosphatase 2A. . Proceedings of the National Academy of Sciences (1992) [DOI]
- Nakatani Takafumi; Konishi Tomoyuki; Miyahara Kazumoto; Noda Naoki. Three Novel Cantharidin-Related Compounds from the Chinese Blister Beetle, Mylabris phalerata PALL. . Chemical and Pharmaceutical Bulletin (2004) [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.
📝 Notes
Public notes from the community and your own private notes on Ban Mao.
No notes yet.