Traditionally used for
- Cough & breathing
- Nerves & recovery
- Skin
Cautions & contraindications
- Pregnancy
- Breastfeeding
- Young children
- Toxic — professional use only
☯ TCM Properties
Removes Putridity and Promotes Tissue Regeneration; Absorbs Dampness and Heals Sores; Promotes Tissue Regeneration and Heals Sores; Kills Parasites and Stops Itching; Descends Qi and Transforms Phlegm; Checks Malaria
Traditional Chinese Uses
Qian Dan (铅丹), Minium, is lead tetroxide (Pb₃O₄), a fine orange-red powder produced by roasting lead. It is acrid and salty and cool and toxic, entering the Heart, Liver and Spleen channels. It removes putridity and promotes the regeneration of tissue, absorbs Dampness to heal sores, and kills parasites to stop itching.
It is an external drug and should be treated as external-only. Its principal role is as the mineral base of traditional black plasters (黑膏药): lead tetroxide is combined with oil to form the plaster mass that carries other medicinals, applied over sores, ulcers, carbuncles and chronic non-healing wounds. It is also dusted on weeping eczema, tinea and foul ulcers.
The classical texts record small internal doses to check malarial disorders and settle convulsions. That use is obsolete and should not be revived. Lead is a cumulative poison with no safe intake: it damages the nervous system, kidneys and haematopoiesis, and children and the unborn are most vulnerable. It is contraindicated in pregnancy. Even in external use, prolonged application over large or broken areas can produce systemic lead absorption, and plasters containing it should not be left on damaged skin for extended periods.
Relationships
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Botanical Description
Qian Dan is not a plant but minium, also called red lead, lead tetroxide (Pb3O4), a toxic heavy-metal oxide. It occurs in nature as the rare mineral minium but in historical TCM practice was manufactured by roasting metallic lead or litharge (PbO) in air, yielding a brilliant scarlet-orange to brick-red, heavy, fine powder with an earthy luster and high specific gravity around 9.0. It is insoluble in water, partially soluble in acids, and decomposes on strong heating. Historically Qian Dan was used externally in plasters and powders for chronic wounds, ulcers, and skin conditions, and occasionally internally; modern toxicology recognizes red lead as a serious source of acute and chronic lead poisoning, and contemporary practice strongly discourages medicinal use (Wikipedia; NCBI).
Active Constituents
Minium (lead tetroxide, Pb3O4)
Mixed-valence lead(II,IV) oxideConcentration: Essentially the whole drug; pure Pb3O4 is 90.7 percent lead by mass, and 16 commercial samples of the same red lead powder sold in Jiangxi averaged 817,000 mg/kg lead
There is no therapeutic constituent here to describe, only a lead dose. Lead has no known threshold below which exposure is harmless, and the WHO position is that no level of lead exposure is known to be without harmful effects. Lead(II) substitutes for calcium and zinc in enzymes and ion channels, inhibits delta-aminolevulinic acid dehydratase and ferrochelatase to produce a microcytic or normocytic anaemia with basophilic stippling, damages the proximal renal tubule, and causes peripheral motor neuropathy and, in children, irreversible loss of cognitive function. Pb3O4 is only slightly water-soluble but dissolves in gastric acid, so oral exposure is real; the mixed-valence oxide is also a strong oxidiser and corrodes tissue on contact.
Litharge and massicot (lead(II) oxide, PbO)
Lead(II) oxide, the tetragonal and orthorhombic mineral formsConcentration: Variable; the intermediate of manufacture and a routine impurity of incompletely oxidised material
Minium is made by roasting lead or litharge in air, so PbO is both the feedstock and the commonest impurity. PbO is separately a traditional drug in its own right, Mi Tuo Seng, which means a patient can receive lead from two nominally different prescriptions. It is more soluble in acid than Pb3O4 and therefore, gram for gram, the more readily absorbed of the two.
Lead carbonate and basic lead carbonate (cerussite and hydrocerussite)
Lead(II) carbonatesConcentration: Trace weathering products on stored material; also the separate drug Qian Fen
Lead oxides carbonate slowly in air. Basic lead carbonate is the classical white cosmetic lead and the drug Qian Fen, which the Chinese Pharmacopoeia still names alongside lead tetroxide as the base for white plasters. Toxicologically it behaves as another lead salt with somewhat greater acid solubility.
Lead soaps (lead oleate, lead palmitate and related fatty acid salts)
Organic lead(II) carboxylates formed during plaster manufactureConcentration: The dominant lead species in a finished black plaster
This is what actually contacts the patient in the commonest modern use. Black plaster is manufactured by heating medicinal materials in edible vegetable oil and then stirring in lead tetroxide, which saponifies with the fatty acids to form the lead soaps that give the plaster its body and its adhesion. The clinically important consequence is that a plaster is not an inert dressing: a 75-year-old man who used a herbal patch on a chronic leg ulcer for three months reached a blood lead of 226 micrograms per dL from a patch assaying 517 mg lead per gram.
Antimony, arsenic, bismuth, silver and cadmium residues from smelted lead
Contaminant metals and metalloids of the parent lead bullionConcentration: Trace, unstandardised, and dependent on whether the lead was of pharmaceutical or industrial origin
Lead tetroxide is a bulk industrial commodity used in paint and lead-acid batteries, and the same material reaches traditional practice. Industrial-grade minium carries the accessory elements of the smelter feed, so the exposure is not necessarily to lead alone. Documented poisonings from Chinese mineral preparations have found lead tetraoxide, arsenic and mercury together in a single product.
⚠ Drug Interactions
Calcium disodium edetate (CaNa2EDTA), succimer (DMSA), dimercaprol and D-penicillamine
Lead chelation is the definitive treatment of plumbism and is effective when the source is removed. In the reported Chinese cases, chelation with cessation of the remedy normalised blood lead and relieved symptoms over two to three treatment rounds (Tang 2017; Ma 2022), but a 51-year-old man poisoned by a hong-dan preparation containing lead tetraoxide, arsenic and mercury retained a peripheral neuropathy four years after chelation (Wu 2013). Chelation without stopping the source simply mobilises lead from a continuing supply, and dimercaprol given alone in lead poisoning can redistribute lead to the brain.
Clinical note: Stop the preparation first. Chelation is a hospital decision guided by blood lead, and the presence of a chelator in the drug history means lead poisoning is already being treated.
Other lead-containing traditional preparations (Mi Tuo Seng / litharge, Qian Fen / lead carbonate, black and white plasters, Ayurvedic and Unani rasa preparations)
Lead reaches patients through several traditional routes at once. In Guangzhou, two children aged three years and six months were hospitalised with blood leads of 303 and 385 micrograms per L after red lead was mixed into talcum and applied to their skin as a baby powder for dermatitis; the powder assayed at 214,000 mg/kg lead, and 16 samples of the red lead itself averaged 817,000 mg/kg, principally Pb3O4 (Lin 2012). Lead tetroxide is also the pharmacopoeial base of black plasters, so a patient can be receiving lead from a prescribed mineral, a plaster and an over-the-counter powder simultaneously. Lead accumulates in bone with a half-life measured in decades, so these exposures add over a lifetime rather than clearing between courses.
Clinical note: Ask specifically about plasters, powders applied to skin, imported remedies and anything given to children in the household. Measure blood lead rather than estimating from the prescription.
Iron and calcium (deficiency, or supplementation for suspected iron-deficiency anaemia)
Lead is absorbed largely through the divalent metal transporter DMT1 in competition with iron and calcium, so iron-deficient or calcium-deficient patients, and young children, absorb a substantially larger fraction of an ingested lead dose. The second problem is diagnostic: lead inhibits haem synthesis and produces an anaemia that is commonly reported as microcytic and readily mistaken for iron deficiency. Reported cases have presented as anaemia with abdominal colic and were identified only when basophilic stippling prompted a blood lead measurement (Ma 2022). Prescribing iron for the anaemia treats the wrong illness while the lead source continues.
Clinical note: In any patient on mineral Chinese medicines with anaemia plus abdominal colic, constipation or peripheral weakness, measure blood lead before treating empirically for iron deficiency. Correcting genuine iron and calcium deficiency does reduce further absorption, but it is not a substitute for removing the source.
Nephrotoxic drugs (NSAIDs, aminoglycosides, ciclosporin) and drugs cleared by glomerular filtration
Lead causes proximal tubular injury acutely and chronic interstitial nephritis with hyperuricaemia on long exposure, and it is itself cleared renally, so declining function raises lead retention. Any concurrent nephrotoxin compounds the injury, and drugs with a narrow therapeutic index cleared by the kidney will accumulate as function falls.
Clinical note: Check baseline creatinine, urate and urine protein, and monitor if exposure has been prolonged. Chronic lead nephropathy is often silent until it is advanced.
Hong Fen (red mercuric oxide, HgO) confused with Hong Dan, a common synonym of Qian Dan
Qian Dan is sold and cited under several red-coloured synonyms including hong dan, huang dan, guang dan and dong dan, while Hong Fen is red mercuric oxide and Hong Sheng Dan is a related mercurial sublimate. The names collide in exactly the way that matters: the two published case reports of poisoning from hong-dan preparations found lead tetraoxide in one product and lead together with arsenic and mercury in another (Lin 2012; Wu 2013), which is to say that what is dispensed under a red-dan name is not reliably a single element. Graded Possible because the frequency of true cross-substitution has not been quantified, but the consequence is that a lead-poisoned patient may be worked up for mercury or the reverse.
Clinical note: Insist on the Latin drug name and an assay, not the pinyin or the colour name. Minium is Pb3O4; Hydrargyri Oxydum Rubrum is HgO. If a patient presents poisoned by a red mineral powder, screen for lead, mercury and arsenic together rather than one at a time.
Pregnancy and breastfeeding (fetal and infant exposure)
Not a drug-drug interaction but the most consequential co-exposure. Lead crosses the placenta by passive diffusion, so fetal blood lead approximates maternal, and maternal skeletal lead is mobilised during pregnancy and lactation, delivering a dose accumulated years earlier. There is no threshold: measurable developmental effects occur at blood leads below the CDC reference value of 3.5 micrograms per dL, which is a population percentile rather than a safe level.
Clinical note: Absolute contraindication in pregnancy, in women who may become pregnant, in breastfeeding and in children. This applies to plasters and topical powders as well as to anything taken by mouth.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| topical | Appropriate amount | — | — | — | No Chinese Pharmacopoeia 2025 monograph for this drug, so no pharmacopoeial dose is given here. EXTERNAL USE ONLY. Lead tetroxide (Pb₃O₄) is the mineral base of traditional black plasters (黑膏药) and is dusted on weeping sores and ulcers. Lead is a cumulative poison with no safe intake — it damages the nervous system, kidneys and haematopoiesis, and children and the unborn are most vulnerable. The classical small internal doses for malarial disorders and convulsions are obsolete and must not be revived. Contraindicated in pregnancy. Even external use should be limited in area and duration and kept off broken skin. The previous value was generic filler generated from tcm_category and has been removed rather than 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
4
4 verified · 0 unverified
Show 4 studies
- Childhood lead poisoning associated with traditional Chinese medicine: A case report and the subsequent lead source inquiry
- Lead, Mercury, and Arsenic Poisoning Due to Topical Use of Traditional Chinese Medicines
- Lead Poisoning Caused by Traditional Chinese Medicine: A Case Report and Literature Review
- Non-occupational lead poisoning associated with traditional Chinese medicine: A case report
In vitro / animal
0
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
Childhood lead poisoning associated with traditional Chinese medicine: A case report and the subsequent lead source inquiry
Two young children from one Guangzhou family, a boy of three and his six-month-old sister, were hospitalised with blood lead levels of 303 and 385 micrograms per L after a traditional powder was used in place of baby powder. The powder assayed at 214,000 mg/kg lead, traced to the addition of hongdan to talcum, and 16 samples of hongdan collected in the source city averaged 817,000 mg/kg lead, principally lead tetraoxide. The authors note that the same lead tetraoxide is an industrial raw material for paint and batteries, and call on Chinese health authorities to re-evaluate the safety of the remedy. This is the clearest published demonstration that the traditional drug and the industrial chemical are the same substance.
Lead, Mercury, and Arsenic Poisoning Due to Topical Use of Traditional Chinese Medicines
Two toxicologically confirmed cases of systemic heavy-metal poisoning from mucocutaneous use of Chinese mineral medicines. A 51-year-old man developed perianal gangrene, high fever, rash, anaemia, hair loss, peripheral neuropathy and muscle atrophy after two weeks of applying a hong-dan mixture containing lead tetraoxide, arsenic and mercury into an anal fistula; DMPS chelation gave only partial improvement and the neuropathy persisted four years later. A 75-year-old man who used a herbal patch on a chronic leg ulcer for three months reached a blood lead of 226 micrograms per dL, the patch assaying 517 mg lead per gram, and recovered after EDTA and DMSA chelation. The authors conclude that short-term application of these preparations to damaged or infected tissue causes serious systemic poisoning.
Lead Poisoning Caused by Traditional Chinese Medicine: A Case Report and Literature Review
A 66-year-old man admitted with periumbilical pain and constipation was found to have a blood lead of 657 micrograms per L after eight months of homemade traditional Chinese medicine; his asymptomatic wife, taking the same preparation, had a blood lead of 488 micrograms per L, and the medicine assayed at more than 4,000 mg/kg lead. Both stopped the medicine and the husband was chelated, with pain relieved and blood lead normal after three rounds. The accompanying review notes that lead-containing bases and pastes are added to herbs both deliberately and inadvertently, and argues that lead exposure from traditional medicine must be considered in unexplained abdominal colic in China.
Non-occupational lead poisoning associated with traditional Chinese medicine: A case report
A 21-year-old man presented with 20 days of severe abdominal pain and constipation after a year of oral Chinese medicine pills and powder taken for facial acne. Blood lead was 1,268.4 micrograms per L against a reference of under 400; he had a moderate normocytic anaemia with haemoglobin 89 g/L, deranged liver function with raised bilirubin, and basophilic stippling on bone marrow examination. The pills assayed at 8,421 micrograms lead per g. He stopped the medicine and was chelated, with symptoms relieved and blood lead normalised after two rounds. The case illustrates how a cosmetic indication and a young healthy patient combine to delay the diagnosis.
Historical Texts
Shen Nong Ben Cao Jing (Divine Husbandman's Classic of Materia Medica), jade and stone section, lower grade, entry for qian dan
Han dynasty, compiled around the first to second century CEBen Cao Gang Mu (Compendium of Materia Medica), Li Shizhen, metal and stone section
Ming dynasty, compiled to 1578, first printed 1596Zhonghua Renmin Gongheguo Yaodian (Pharmacopoeia of the People's Republic of China), 2020 edition, Part IV, general chapter 0186 for plasters
People's Republic of China, 2020References
- Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for Lead . U.S. Department of Health and Human Services, Public Health Service, Atlanta GA (2020)
- World Health Organization. Chemical safety: Lead poisoning . World Health Organization questions and answers (2024)
- Ko RJ. Adulterants in Asian Patent Medicines . New England Journal of Medicine (1998) [DOI]
- Chinese Pharmacopoeia Commission. Zhonghua Renmin Gongheguo Yaodian 2020, Part IV, general chapter 0186: Gao Yao (Plasters) . Pharmacopoeia of the People's Republic of China, 2020 edition (2020)
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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