Hei Xi (Lead)

Chinese Herb Actions

Chinese Herb Dosage

• What is the dosage of Hei Xi (lead)?

  No dosage is published on this page, and no safe dose exists to publish. Lead is a cumulative poison: what enters the body is absorbed, stored in bone over years, and released slowly back into the blood. There is no threshold below which lead exposure has been shown to be harmless, so there is no quantity that could responsibly be presented as a dose.

  Publishing a figure would also imply that the substance is obtainable and usable, which it is not. Lead is not supplied by legitimate herbal pharmacies, is not dispensed by qualified practitioners, and is regulated as a toxic metal rather than as a medicinal ingredient.

  Readers studying classical formula literature for scholarship or exams should treat the lead-containing prescriptions as historical texts. Anyone who suspects they have taken a lead-containing preparation should stop and seek medical assessment, including blood lead testing — that is a clinical matter, not a herbal one.

  Sources: PMID 29026055, DOI 10.12809/hkmj176214 (no safe blood lead level); PMID 30990555, DOI 10.1001/jama.2019.1004 (elevated blood lead is associated with serious, often irreversible health consequences). Reference statement only.

Chinese Herb Contraindications & Cautions

• Is Hei Xi (lead) safe, and is it legal to use?

  It is not safe at any exposure level, and it is not a legitimate medicinal ingredient. Lead is regulated internationally as a toxic metal and as an industrial contaminant; medicinal products found to contain it are typically the subject of recalls and public-health warnings rather than of dosing guidance. Qualified practitioners do not use it, and reputable pharmacies do not supply it.

  • Exposure is cumulative and largely irreversible. Lead follows multi-compartment kinetics with its longest residence time in bone, so repeated small exposures build a body burden that persists for years. Elevated blood lead is associated with serious and often irreversible harm.
  • Children are the most vulnerable group. Childhood lead exposure damages neurodevelopment, and the damage is not undone by later removal of the source. Lead also crosses the placenta, so exposure in pregnancy reaches the fetus.
  • Poisoning is easily missed. Reported presentations from traditional-medicine lead poisoning include cramping periumbilical abdominal pain, constipation, anaemia with basophilic stippling of red cells, and non-specific fatigue — a picture that is frequently misattributed to other causes until a medication history is taken and blood lead is measured.
  • Household exposure is not limited to the person taking the product. In one reported case, the asymptomatic spouse of a patient who had been taking a homemade lead-containing preparation also had a markedly elevated blood lead level.

  If lead exposure is suspected, this is a medical problem. Diagnosis rests on blood lead measurement, and treatment (including whether chelation is appropriate) is a clinical decision made by a physician or poisons service. Nothing on this page should be used to self-assess or self-treat.

  Sources: PMID 29026055, DOI 10.12809/hkmj176214 (no safe blood lead level; childhood lead poisoning overview); PMID 30990555, DOI 10.1001/jama.2019.1004 (serious, often irreversible consequences; screening in childhood and pregnancy); PMID 29081456, DOI 10.1620/tjem.243.127 (periumbilical pain, constipation, anaemia; affected spouse); PMID 39066909, PMC 11787186, DOI 10.1007/s00210-024-03317-y. Neutral reference facts; not medical advice.

Chinese Herb Toxicity & Overdose

• How toxic is lead, and what does it actually do in the body?

  Lead is one of the most thoroughly documented toxicants in environmental medicine, and no safe level of exposure has been identified. It is absorbed, distributed to blood and soft tissue, and then stored in the skeleton, from which it is released slowly for years afterwards. Its most important effect is neurotoxicity, and its most vulnerable target is the developing brain.

  • Cognitive harm at low levels, and it is irreversible. An international pooled analysis of seven birth cohorts (1,333 children) found an inverse relationship between blood lead concentration and full-scale IQ, with the steepest per-unit losses occurring at the lowest exposures — that is, harm continues below the concentrations once treated as an action threshold, and does not have a clean cut-off.
  • The population-level burden is large. A 2023 global modelling analysis in The Lancet Planetary Health estimated IQ loss in children under five and cardiovascular deaths in adults attributable to lead exposure worldwide, with substantial associated economic cost — so lead's effects are not confined to acute poisoning cases.
  • Acute and subacute poisoning. Reported features include colicky abdominal pain, constipation, anaemia with basophilic stippling, fatigue, irritability, peripheral neuropathy, and in severe cases encephalopathy.
  • Documented from medicinal sources, at high concentrations. In one case report, a 66-year-old man taking a homemade traditional preparation for eight months had a blood lead level of 657 µg/L, and chemical analysis of the preparation found more than 4,000 mg/kg of lead. Non-occupational lead poisoning traced to traditional medicine has been reported separately.
  • Contamination is a live, ongoing issue. Reviews of metal contamination in traditional medicines emphasise the absence of internationally harmonised processing and manufacturing standards, and repeated case reports of poisoning across Asia, Europe and North America.

  Sources: PMID 16002379, PMC 1257652, DOI 10.1289/ehp.7688 (international pooled analysis; IQ decrement, steeper at low blood lead); PMID 37714172, DOI 10.1016/S2542-5196(23)00166-3 (global burden and cost of lead exposure); PMID 29026055, DOI 10.12809/hkmj176214; PMID 30990555, DOI 10.1001/jama.2019.1004; PMID 29081456, DOI 10.1620/tjem.243.127 (657 µg/L case; >4,000 mg/kg in the preparation); PMID 36176514, PMC 9513390, DOI 10.3389/fpubh.2022.938186 (non-occupational lead poisoning from traditional medicine); PMID 25048473, PMC 4108800, DOI 10.3349/ymj.2014.55.5.1177; PMID 39066909, PMC 11787186, DOI 10.1007/s00210-024-03317-y. Toxicological reference; no dosing or usage information is given or implied.

• 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

• Does Hei Xi (lead) interact with medications?

  This is not a herb–drug interaction question, and framing it that way would be misleading. Lead is a poison rather than a therapeutic agent, so the clinically relevant relationship with medication is the opposite of an interaction: chelating agents are drugs given to remove lead from the body, and their use is a physician-directed treatment for confirmed poisoning, not a countermeasure that makes exposure acceptable.

  The genuinely useful point for readers is different: because lead can be present in traditional preparations as a contaminant or an undeclared ingredient, a full medication and supplement history — including imported, homemade and non-prescription remedies — is what allows clinicians to recognise lead poisoning at all. Several published cases were diagnosed only once that history was taken.

  Sources: PMID 29081456, DOI 10.1620/tjem.243.127 (diagnosis followed a detailed medication history; chelation given as treatment); PMID 30990555, DOI 10.1001/jama.2019.1004 (screening and treatment evidence review); PMID 39066909, PMC 11787186, DOI 10.1007/s00210-024-03317-y. Reference information only.

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 Hei Xi (lead)?

  Yes — an enormous body of it, and essentially none of it is therapeutic research. The literature on lead is toxicology, epidemiology, public health and clinical poisoning management. There is no contemporary programme investigating lead as a medicine, and there could not legitimately be one.

  • Neurodevelopmental epidemiology — the pooled analysis of seven international birth cohorts remains the reference work linking childhood blood lead to IQ deficits, and is notable for finding proportionally greater losses at lower exposures.
  • Global burden modelling — a 2023 analysis quantified childhood IQ loss and adult cardiovascular mortality attributable to lead worldwide, together with the economic cost, using Global Burden of Disease blood lead estimates.
  • Traditional-medicine poisoning — case reports and reviews document lead poisoning traced to traditional preparations, including a case with a blood lead level of 657 µg/L from a homemade remedy containing over 4,000 mg/kg lead, a separate non-occupational poisoning case, and a systematic analysis of 210 published patient cases in which lead and arsenic were the metals most frequently implicated.
  • Contamination surveillance — clinical reviews of metal contamination in traditional medicines describe the regulatory gap and argue for education of both clinicians and patients about the risk.
  • Screening and management — systematic review work for preventive-services guidance has assessed screening, testing and treatment for elevated blood lead in children and in pregnancy.

  What this means for a reader of a classical text. The direction of travel in the evidence has been consistently one way: each generation of studies has found harm at lower exposures than the last. That is the reason lead-containing preparations were abandoned rather than merely dose-limited.

  Sources: PMID 16002379, PMC 1257652, DOI 10.1289/ehp.7688; PMID 37714172, DOI 10.1016/S2542-5196(23)00166-3; PMID 29081456, DOI 10.1620/tjem.243.127; PMID 36176514, PMC 9513390, DOI 10.3389/fpubh.2022.938186; PMID 39066909, PMC 11787186, DOI 10.1007/s00210-024-03317-y; PMID 25048473, PMC 4108800, DOI 10.3349/ymj.2014.55.5.1177; PMID 30990555, DOI 10.1001/jama.2019.1004; PMID 29026055, DOI 10.12809/hkmj176214. Research context, not a therapeutic claim.

Chinese Herb Notes

• Which formula on this site contains Hei Xi, and why does a lead entry exist at all?

  One formula in our records carries it: Hei Xi Dan (“Lead Special Pill”), recorded for kidney yang devastation with floating yang — the Kidneys failing to grasp the qi. Our formula record already states plainly that Hei Xi Dan is toxic by design, is a historical and encyclopedic record only, and carries no administration or dosing instructions. Alongside lead, its recorded composition includes Liu Huang (sulfur) and Fu Zi (processed aconite), both independently flagged as toxic on this site, plus warming and qi-moving herbs such as Rou Gui, Chen Xiang, Mu Xiang, Bu Gu Zhi and Xiao Hui Xiang.

  Why the record exists. Metals and minerals were a real branch of historical pharmacy in China and elsewhere — lead, mercury, arsenic and sulfur all appear in classical texts, and lead compounds appear in the historical materia medica of Europe, South Asia and the Middle East too. Documenting that honestly is part of documenting the tradition. Presenting it as a live therapy would not be.

  The practical reason readers arrive here. Lead contamination of traditional medicines is itself a documented public-health problem. It arises two ways: from deliberately included mineral ingredients, and from contamination or adulteration of otherwise ordinary herbal products. A systematic analysis of 210 published patient cases of metal poisoning from traditional and alternative medicines found lead and arsenic to be the metals most often involved, with most implicated products originating in Asia. A clinical review from Korea reached the same conclusion, noting that no international standardisation of processing and manufacturing exists and that unacceptably high metal levels can be present in preparations.

  Sources: our own formula record for Hei Xi Dan (composition, pattern, and existing cautions); PMID 39066909, PMC 11787186, DOI 10.1007/s00210-024-03317-y (210 patient cases; lead and arsenic predominate); PMID 25048473, PMC 4108800, DOI 10.3349/ymj.2014.55.5.1177 (metal contamination of traditional medicines; absence of international manufacturing standards). Historical and public-safety reference.

This herb is toxic or restricted in the United States