Bloodroot

What is Bloodroot?

Bloodroot is Sanguinaria canadensis L., the only species in its genus, a spring ephemeral in the poppy family (Papaveraceae) that flowers across eastern North America from Nova Scotia to Florida and west to Manitoba before the forest canopy closes. Cut the horizontal rhizome and it bleeds an orange-red latex, which is where both the common name and the Latin sanguinaria come from. That latex is a concentrated alkaloid solution, and its principal component, sanguinarine, is a quaternary benzophenanthridine alkaloid that destroys living tissue on contact. Bloodroot is the botanical basis of "black salve," the escharotic paste the US Food and Drug Administration named in a "Do Not Use" consumer advisory published 13 October 2020 after reviewing 24 adverse event reports, 15 of them from the preceding five years, including at least one death.

Common Names

• Bloodroot, blood root, red puccoon, red root, Indian paint, tetterwort

• Sanguinaria, sanguinaria extract (SaE), the labeling term used in oral care products

• Black salve, red salve, drawing salve, Cansema, Indian Herb, Hawk Dok Natural Salve, Black Drawing Ointment, all names the FDA listed in its 2020 advisory for bloodroot-containing escharotic pastes

• Compound X, a current retail name for a black salve product

Primary Active Compounds

• Sanguinarine, the dominant quaternary benzophenanthridine alkaloid and the caustic agent

• Chelerythrine, a second quaternary benzophenanthridine, a protein kinase C inhibitor, present at concentrations close to sanguinarine

• Sanguilutine, chelilutine, chelirubine and sanguirubine, minor quaternary benzophenanthridines

• Protopine and allocryptopine, tertiary protopine-type alkaloids

• Berberine, present only in trace amounts in Sanguinaria, not a principal constituent despite frequent listing

Key Note

Slavik's classic 1960 fractionation of the rhizome alkaloid pool put sanguinarine at 36.5 percent and chelerythrine at 33.4 percent of total alkaloids, with sanguilutine at 9.1 percent, chelilutine 7.8 percent, allocryptopine 4.2 percent, protopine 4.1 percent, chelirubine 2.5 percent and sanguirubine 1.2 percent. What that clean profile hides is the raw variability. A survey of 100 wild populations found sanguinarine ranging from 0.6 percent to 6.3 percent of rhizome dry weight, averaging 2.7 percent, with up to 15-fold differences between individual rhizomes. Graf and colleagues (J Agric Food Chem 2007;55(4):1205-1211) found wildcrafted material consistently richer in sanguinarine and chelerythrine than cultivated material, and consistently more variable.

Bloodroot has three separate commercial lives: a caustic sold as a cancer cure, an antiplaque agent that spent roughly eighteen years in American bathrooms before its active was quietly removed, and a traditional expectorant still sold as capsule and tincture. All three run on the same molecule.

Primary Functions & Benefits

Bloodroot has no established therapeutic function in humans that survives contact with a controlled trial. What it has is three documented pharmacological actions, each of which has been marketed as a benefit.

Tissue destruction (escharotic action)

Applied to skin at salve concentrations, sanguinarine produces coagulative necrosis, then an eschar, then a slough. Nobody disputes this. The dispute is only over whether it is a treatment.

Antimicrobial and antiplaque action

Eisenberg and colleagues (Caries Res 1991;25(3):185-190) reported minimum inhibitory concentrations for sanguinarine of 4 to 8 micrograms per milliliter at pH 6.5 against Streptococcus mutans, S. sobrinus, S. sanguis, Actinomyces viscosus and A. naeslundii, synergistic with zinc. This is the pharmacology that put bloodroot into toothpaste.

Emetic and expectorant action

Small oral doses provoke bronchial secretion, larger doses provoke vomiting, with emesis reported from roughly 30 mg of powdered root. There is no modern controlled trial of bloodroot for cough, bronchitis, asthma or any respiratory indication.

What is not on this list

There is no human trial showing bloodroot cures any cancer, benign lesion, wart, mole or skin tag. Lim's 2018 review in the Journal of Dermatological Treatment (29(4):388-392) found the entire clinical literature on black salve consists of case reports describing suboptimal therapeutic and cosmetic outcomes.

Forms & Standardization

There is no standardized bloodroot product on the consumer market. This section is therefore the toxicology of each form sold, not a bioavailability comparison.

Black salve / escharotic paste

Bloodroot powder or extract combined with zinc chloride, usually in a base with glycerin, chaparral, graviola or DMSO depending on maker. There is no reference formula and no disclosed sanguinarine content on any product the FDA has cited. Croaker's group (BMC Complement Med Ther 2022;22:247) measured 24-hour half-maximal inhibitory concentrations for sanguinarine of 2.1 micromolar against the A375 melanoma line and 3.14 micromolar against the A431 squamous cell carcinoma line, more cytotoxic at 24 hours than 5-fluorouracil, the actual topical drug for superficial skin cancer. Lim's review notes that above roughly 5 micromolar the destruction becomes indiscriminate between malignant and normal cells. A paste applied to skin is not delivering micromolar concentrations, it is delivering percent concentrations, which is why the tissue effect is a burn rather than a selective kill.

Mole and skin tag removers

The same chemistry sold at lower stated strength for cosmetic use. FDA's 6 October 2020 warning letter to Haloderm, Inc. of Carlsbad, California cited HaloDerm Regular and HaloDerm Advanced "Homeopathic Mole & Skin Tag Remover," both containing bloodroot and zinc chloride, as unapproved new drugs under sections 505(a) and 301(d) of the Federal Food, Drug, and Cosmetic Act. The letter stated plainly that the combination of bloodroot and zinc chloride produces a corrosive topical agent.

Oral care extract (historical)

Sanguinaria extract standardized as a percentage of the finished product, not of alkaloid. The Viadent dentifrice contained 0.075 percent sanguinaria extract with 2.0 percent zinc chloride. The Viadent oral rinse contained 0.03 percent sanguinaria extract with 0.2 percent zinc chloride, which Etemadzadeh and Ainamo (J Clin Periodontol 1987;14(3):176-180) recorded as equivalent to 0.01 percent sanguinarine chloride. Those two numbers, 0.075 percent and 0.03 percent, are the only well-documented standardizations bloodroot has ever had, and both products are gone.

Tincture

Typically 1:5 in 40 to 60 percent alcohol, sold in 30 mL and 60 mL bottles, label serving usually 5 to 15 drops. No marker compound percentage is declared on any consumer tincture reviewed. Given the 0.6 to 6.3 percent dry-weight range for sanguinarine in wild rhizome, two tinctures made to the same 1:5 ratio can differ tenfold in alkaloid delivered.

Capsule

Powdered rhizome, commonly 450 to 500 mg per capsule, occasionally sold as a 4:1 extract with no marker assay. A single 500 mg capsule of a high-alkaloid rhizome lot could carry over 30 mg of sanguinarine, which is in the range at which vomiting has been documented.

Veterinary and feed use, and the substitution nobody mentions

Sanguinarine is sold worldwide as a livestock feed additive under the trade name Sangrovit. That product is made from Macleaya cordata, the plume poppy, a different genus in the same family, and it is the Macleaya article that holds European Food Safety Authority opinions (Sangrovit Extra for poultry, 2023, and for piglets and growing Suidae, 2024). Sanguinaria canadensis itself is not the authorized feed source. Any supplement invoking "the sanguinarine used safely in animal feed" is invoking a different plant.

Food Sources

Bloodroot is not a food and has never been one. This section is routes of exposure.

• Topical escharotic products. The dominant exposure. Sold online as black salve, red salve, drawing salve, Compound X, and as mole and skin tag removers. Konkel and colleagues at FDA's Division of Pharmacovigilance (J Clin Aesthet Dermatol 2023;16(1):14-17) assembled 38 cases of serious skin injury from unapproved mole and tag removers, 30 drawn from Amazon consumer reviews and 8 reported to FDA, with 28 of the 38 occurring in 2021 alone. Fourteen were facial injuries and four were adjacent to the eye.

• Oral care products, historical. Between 1983 and 2001, twice-daily brushing plus rinsing with the sanguinaria regimen was a routine, years-long, whole-mouth mucosal exposure for a large American consumer population. This is the largest deliberate human exposure bloodroot has ever had.

• Oral supplements, current. Capsules and tinctures sold as expectorant, "blood purifier" and dental rinse additive.

• Ornamental and wild plants. The whole plant is toxic if eaten. Root latex is the most concentrated part. The double-flowered cultivar 'Multiplex' is widely sold as a garden plant and is chemically the same species.

• Adulterated cooking oil, a separate and instructive route. Sanguinarine is the alkaloid implicated in epidemic dropsy, the outbreak illness caused by mustard oil adulterated with argemone oil from Argemone mexicana seed. Croaker and colleagues (J Appl Toxicol 2018;38(10):1274-1281) noted that black salve contains sanguinarine at concentrations substantially higher than the contaminated massage oils that have caused dropsy through skin contact.

There is no dietary requirement for bloodroot and no food that supplies it. The honest instruction here is not "eat the food, skip the pill." It is that there is no food, and the pill has nothing to recommend it.

Who Should Take Bloodroot

No one should apply bloodroot to skin. That is not a cautious framing, it is the position of the FDA, the American Academy of Dermatology, Australia's Therapeutic Goods Administration and New Zealand's Medsafe. There is no lesion, benign or malignant, for which a self-applied caustic is the correct answer.

Who is likely to encounter it anyway

• People with a biopsy-confirmed skin cancer who are afraid of surgery, particularly on the face. This is the recurring profile in the case literature.

• People in rural areas. Croaker's Australian series found black salve use rose with rurality on the Modified Monash scale, consistent with distance from dermatological services.

• People whose lesion is not cancer at all. In the 475-lesion Australian series, 18 percent of treated sites were benign, meaning the salve was destroying healthy tissue for nothing.

• Anyone who used Viadent regularly before 2001 and has never had the maxillary vestibule examined.

Who should be checked rather than treated

Anyone with a persistent white patch in the upper labial or buccal vestibule and a history of sanguinaria-containing oral care products should have it examined and, if it persists, biopsied. Allen and colleagues (Gen Dent 2001;49(6):608-614) recorded that discontinuing the product often does not resolve the lesion.

The comparison that settles it

Mohs micrographic surgery, the technique that actually descends from escharotic pastes, reports five-year recurrence rates for basal cell carcinoma as low as 1 percent, and Robins' 1980 series of 2,900 cases recorded 98.2 percent cure for primary basal cell carcinomas and 96.6 percent for recurrent ones. Those figures exist because the surgeon reads the margin under a microscope. Black salve produces no margin to read.

Who Should AVOID or Use Caution

Contraindications

• Anyone with a suspected or confirmed skin malignancy. Every recorded harm sequence begins here.

• Pregnancy and breastfeeding. Bloodroot has documented emmenagogue and uterine-stimulant activity.

• Any application to the face, eyelid, nose, ear, lip, genitalia or breast. Bozung and colleagues (Ophthalmic Plast Reconstr Surg 2021;37(2):e71-e73) described a 65-year-old woman who self-treated a medial canthal basal cell carcinoma, developed cicatricial lower lid ectropion with punctal obliteration, and was found on biopsy to still have basal cell carcinoma inside the scar tissue. She then needed Mohs surgery plus multistage reconstruction.

• Mucosal application of any kind. Ayoub and Parise (Ochsner J 2020;20(4):456-458) reported a 33-year-old woman who applied black salve intravaginally for cervical intraepithelial neoplasia and was later found on hysteroscopy to have vaginal scarring forming a blind pouch that concealed the cervix.

• Children, and any household where a caustic paste could be reached.

Use Caution

• Oral bloodroot at any dose. The emetic threshold is low and poorly defined, with vomiting reported from roughly 30 mg of powdered root.

• Concurrent digoxin or other cardiac glycosides. Sanguinarine inhibits Na+/K+-ATPase with a half-maximal inhibitory concentration of 6.0 to 6.5 micromolar, the same target as digoxin.

• Glaucoma history. Sanguinarine exposure is associated with glaucoma in the epidemic dropsy literature.

• Sanguinaria-containing oral rinses of any provenance, including recent artisan reintroductions.

Critical Safety Point

The most dangerous property of black salve is not the burn, it is the delay. McDaniel and Goldman (Arch Dermatol 2002;138(12):1593-1596) described a patient whose nasal basal cell carcinoma appeared "healed" for several years after escharotic treatment elsewhere, then recurred deeply, required extensive resection and subsequently metastasized. Sivyer and Rosendahl (Dermatol Pract Concept 2014;4(3):77-80) followed a woman who applied black salve to a thin superficial spreading melanoma; five years later the melanoma persisted and had spread to regional nodes, lungs, liver, subcutaneous tissue and muscle. A visibly healed surface over an untreated tumor is the worst possible outcome, because it buys silence.

Recommended Dosages

There is no recommended dosage of bloodroot for any purpose, and no regulatory body anywhere has set one. The figures below are historical and toxicological reference points, not amounts to take.

Escharotic paste

No dose exists. FDA's position, stated in warning letters to Healing Within Products & Services, Inc. (17 April 2017) and Haloderm, Inc. (6 October 2020), is that these are unapproved new drugs and misbranded under sections 201(g)(1), 301(d), 505(a) and 502(f)(1) of the Federal Food, Drug, and Cosmetic Act. A product with no lawful marketing status has no dosage.

Historical oral expectorant reference

Nineteenth-century Western practice used 1 to 2 grains every two hours as an expectorant, one grain being about 64.8 mg, so roughly 65 to 130 mg of powdered root. This is recorded here as pharmacy history. It predates any toxicology on sanguinarine.

Historical emetic reference

Larger doses were used deliberately to induce vomiting. The modern observation that emesis can follow roughly 30 mg means the historical expectorant and emetic ranges overlap, which is another way of saying the drug had no usable therapeutic window even by the standards of the era that used it.

Current retail labels

Capsules commonly declare 450 to 500 mg powdered rhizome per capsule; tinctures commonly declare 5 to 15 drops. Neither declares sanguinarine content. Given documented rhizome sanguinarine of 0.6 to 6.3 percent dry weight, a 500 mg capsule spans roughly 3 mg to 31 mg of sanguinarine depending entirely on which rhizome was ground.

Oral care reference, historical

0.075 percent sanguinaria extract in dentifrice and 0.03 percent in rinse, twice daily. This is the only bloodroot regimen ever studied in a six-month controlled trial, and it is the regimen the leukoplakia epidemiology is about.

Duration

Not applicable, because no use is recommended. For the historical oral care exposure, the epidemiological signal is tied to chronic use measured in years, not to short courses.

Timing & Administration

Because no use is recommended, this section describes what people actually do, which is clinically useful.

Topical application

Vendors instruct users to apply the paste under an occlusive dressing for 24 hours, remove it, and wait. Amid-Toby and Sequeira (Cureus 2025;17(11):e96519) published a case in which the patient photographed every stage. The necrotic plug then separates over roughly two to three weeks, and vendors call that plug a tumor. Leecy and colleagues (Pathology 2013;45(7):670-674) reviewed 16 lesions from 11 patients and found what it actually consists of: scarring, granulomatous inflammation, implanted foreign material, reactive stromal atypia and suppurative necrosis, with residual neoplasia still present in 2 of the 16.

Repeat application

The pattern in the case reports is a second course when the lesion returns. In Cienki and Zaret's first case, a 53-year-old man applied salve for 10 days, saw the lesion regrow after six months, restarted despite intense pain, and after six weeks the lesion had doubled, ulcerated and suppurated. Biopsy showed malignant melanoma.

Oral administration

Historically taken between meals in water. The emetic effect is dose-limiting and arrives quickly.

Practical instruction

If a salve has already been applied, stop, do not reapply, and take the product and its packaging to a clinician. Adverse events can be reported to FDA MedWatch at 1-800-332-1088.

Timeline of Effects

Hours 0 to 24

Burning and pain at the application site. Laskey and Tran (Clin Toxicol 2017;55(7):676-677) reported an 86-year-old man who applied a single dose of black salve to a mole and progressed to blackening and swelling; two weeks later he arrived at a trauma bay with profuse bleeding from the left temple and a raised 2 cm eschar.

Days 2 to 7

Eschar formation. Users read the blackening as the product "working." It is coagulative necrosis.

Weeks 2 to 3

Slough separation, leaving an ulcer. This is the moment vendors present as cure.

Weeks 3 to 12

Secondary healing by contraction. Scarring is the rule, not the exception. Worley and colleagues (J Drugs Dermatol 2018;17(6):683-685) described a 78-year-old man with a biopsy-proven atypical fibroxanthoma of the scalp who applied black salve and presented with a severe burn covering 20 percent of his scalp, requiring hospital admission and multi-stage reconstruction with head and neck surgery.

Months 6 to 60, the interval that matters

This is where treatment failure declares itself. McDaniel and Goldman's nasal case appeared healed for several years before deep recurrence and metastasis. Sivyer and Rosendahl's melanoma case declared at five years. Bozung's periorbital case presented 1.5 years after diagnosis with residual carcinoma inside the scar. Duncanson and colleagues (J Clin Aesthet Dermatol 2019;12(1):28-31) reported a 47-year-old woman who had been treating a growing mole with black salve for several years and presented with a 9.7 cm by 8.3 cm fungating melanoma on her foot that prevented her from walking.

Fair trial

There is no fair trial to define, because the endpoint that matters, clearance of tumor at the margin, cannot be assessed without a specimen. For a surgical excision the trial ends when the pathologist reads the margin. For an escharotic it never ends. The oral care exposure ran on the same mismatch: Harper's six-month trial (J Periodontol 1990;61(6):352-358, n=60) reported the efficacy result, and the leukoplakia signal took years of consumer use to surface.

Benefits of Taking Bloodroot

There are no established benefits of taking bloodroot, orally or topically. What follows is history, framed as history.

The escharotic tradition

Jesse Weldon Fell, an American physician working in London, published a zinc chloride and bloodroot paste for breast tumors in the Lancet in 1857. That lineage runs forward into Frederic E. Mohs, who began developing his technique in 1933 and treated his first human patients in 1936 using a fixative paste of zinc chloride, stibnite and Sanguinaria canadensis. The critical detail is what Mohs added: he excised the fixed tissue and mapped it under a microscope, layer by layer, until the margins were clear. Mohs experimented with a fresh-tissue technique in 1953 and the field moved to it through the 1970s. The paste was dropped. The microscopy was kept. Black salve is the half Mohs discarded.

The oral care episode

Sanguinaria extract with zinc chloride did produce measurable reductions in plaque and gingivitis in company-run six-month trials. Independent work was less kind: Etemadzadeh and Ainamo's crossover study in 12 dental students found the Viadent rinse produced no significant plaque reduction compared with tap water, while 0.2 percent chlorhexidine did. Vlachojannis, Magora and Chrubasik (Phytother Res 2012;26(10):1423-1426) concluded that neither the toothpaste nor the mouthwash showed demonstrable clinical effectiveness when tested separately, and that later combined-use studies gave conflicting results.

The traditional use

Native American and later Eclectic practice used bloodroot as an expectorant, an emetic, a topical for skin lesions, a dye and a component of poultices. No modern controlled human trial exists for any of these indications.

In-vitro cytotoxicity, said plainly

Sanguinarine really is cytotoxic to cancer cell lines in culture, and it is potent. That is where the marketing gets its foothold, and it is a genuine finding, not an invention. It is also not evidence of anything clinically useful, because sanguinarine is a general-purpose caustic. Household bleach kills cancer cells in a dish too. So does zinc chloride, which is why it is in the paste. A compound that kills every cell type it meets will always score well in a cytotoxicity assay, and that score carries no information about whether it can distinguish tumor from the nose it is sitting on. Croaker's own assay work makes this explicit: every black salve constituent tested was more cytotoxic to skin cancer cell lines at 24 hours than 5-fluorouracil, and the group's conclusion was that black salve therefore likely possesses normal tissue toxicity, with some cancer lines relatively resistant.

Potential Negatives & Side Effects

Topical

• Full-thickness chemical burn, coagulative necrosis, ulceration.

• Permanent scarring and disfigurement. Saltzberg, Barron and Fenske titled their 2009 report in Dermatologic Surgery (35(7):1152-1154) "Deforming self-treatment with herbal 'black salve'."

• Destruction of cartilage and specialized structures. Osswald and colleagues (J Am Acad Dermatol 2005;53(3):509-511) described a large nasal ulceration in a woman who applied "black and yellow salves" obtained in Mexico to a basal cell carcinoma.

• Hemorrhage. See the temple bleed in Laskey and Tran.

• Fistula formation. Cienki and Zaret's second case involved a 42-year-old man with metastatic colon cancer whose mother bought black and yellow bloodroot salve for abdominal wall nodules; after 8 days feces were discharging from the ulcer, and he required total parenteral nutrition.

• Infection requiring hospitalization and grafting. Hakim, Cascardo and Pedersen (JAAD Case Rep 2025;66:52-54) reported hospitalization and extensive tissue damage after self-treatment of a melanoma in situ with Compound X.

• Persistence of the underlying cancer, at 34.2 percent of malignant treatment sites in the Australian pathology series.

Oral mucosal and systemic

Sanguinaria-associated leukoplakia of the maxillary vestibule, graded in the research section below, frequently does not resolve on stopping the product. Oral ingestion gives nausea, vomiting and gastric burning, and in overdose hypotension, bradycardia and central nervous system depression. The epidemic dropsy risk (edema, cardiac and ocular effects) from high sanguinarine loads is theoretical for salve users and has not been observed clinically to date.

Deficiency Symptoms

Nobody has ever been short of bloodroot, and nobody can be. No human enzyme, transport protein or metabolic pathway requires sanguinarine, chelerythrine or protopine, so there is nothing to run low on. Contrast this with a genuine trace element like iodine, where absence produces goiter, cretinism and measurable thyroid hormone deficits at population scale, with a defined Recommended Dietary Allowance of 150 micrograms per day for adults. Nothing comparable exists for bloodroot at any intake, including zero.

What bloodroot addresses

Nothing that has survived a controlled test in people. The historical claims are expectoration, emesis, plaque control and lesion destruction. Of these, plaque control was tested and produced conflicting results before the product was reformulated, and lesion destruction is real but non-selective. Expectoration and emesis have never been tested in a modern trial.

Bottom line

A person who never encounters bloodroot in any form has no gap to fill and no risk to manage. That is the whole of the deficiency question.

Toxicity Symptoms

At high intake

Oral: vomiting from roughly 30 mg of powdered root upward, with gastric burning, intense thirst, dizziness and visual disturbance reported historically. Sanguinarine inhibits Na+/K+-ATPase with a half-maximal inhibitory concentration of 6.0 to 6.5 micromolar; in guinea pig atria this raises intracellular sodium, activates the sodium-calcium exchanger and raises intracellular calcium, a digoxin-like action. Large ingestions are therefore a cardiac question, not only a gastrointestinal one.

Topical: the toxicity is the intended effect. There is no "high dose" distinct from the ordinary dose, only more tissue destroyed.

Signs to reduce or stop

• Any blackening, blistering, weeping or expanding pain at an application site. Stop immediately and seek assessment. Do not wait for the eschar to separate.

• A white patch in the upper labial or buccal vestibule.

• Persistent vomiting, palpitations, visual change or lower limb edema after oral use.

• Bleeding from a treated site, which can be arterial.

General note

Sanguinarine's carcinogenic status is unresolved rather than cleared. Croaker and colleagues reviewed it in Mutation Research Reviews (2017;774:46-56) and found genuinely contradictory in-vitro and in-vivo genotoxicity and rodent carcinogenesis results, while noting that sanguinarine's structure resembles known polycyclic aromatic carcinogens, that it intercalates DNA, and that epidemiology has linked sanguinarine mouthwash to oral leukoplakia. Their conclusion was that the question is urgent precisely because patients apply the compound to sun-damaged skin already carrying field change. "Not proven carcinogenic" and "shown to be safe" are different statements, and only the first one applies.

How Bloodroot Works

Sanguinarine is an iminium salt, and pH decides what it does

Sanguinarine exists in two interconverting forms: a positively charged iminium species dominant between pH 2 and 6, and an uncharged alkanolamine species dominant between pH 6.5 and 9.0. The alkanolamine is far more lipophilic and penetrates cells much more readily. This single equilibrium explains a great deal about why the compound behaves inconsistently, because tissue pH, formulation pH and the acidity of a mouth after eating all shift which species is present.

The caustic action

The charged iminium form is a strong electrophile that reacts with nucleophilic sites on proteins, thiols in particular. At the concentrations present in a salve it denatures structural and enzymatic proteins across whatever cells it contacts, producing coagulative necrosis. Zinc chloride adds a second, independent mechanism: it is a hygroscopic Lewis acid that dehydrates and fixes tissue. Neither mechanism has any capacity to identify a malignant cell. This is why the pastes destroy healthy skin, cartilage, eyelid, breast tissue and vaginal mucosa with the same efficiency they destroy a tumor, and why the Australian pathology series found necrosis of normal tissue at sites where the target lesion had been benign all along.

The intracellular actions at low concentration

Below the caustic range, sanguinarine intercalates DNA, generates reactive oxygen species, triggers endoplasmic reticulum stress and the unfolded protein response, produces 8-hydroxyguanine lesions, and inhibits Na+/K+-ATPase. Chelerythrine, the second major alkaloid, inhibits protein kinase C. These are the mechanisms that generate the impressive in-vitro cancer papers, including recent work identifying sanguinarine chloride as a telomerase inhibitor (Cells 2022;11(9):1485). They are also mechanisms of general cellular toxicity, which is the point.

Why the leukoplakia sits where it sits

At 4 to 8 micrograms per milliliter sanguinarine disrupts bacterial membranes, potentiated by zinc, which is what a rinse was meant to do to plaque biofilm. The same rinse reached keratinocytes twice a day for years. The maxillary vestibule is a fold where fluid pools, so it collects the lipophilic alkanolamine fraction and receives a longer, higher effective exposure than mucosa washed by saliva flow. The anatomical distribution of the lesions is itself evidence for the causal story.

Synergistic Supplements

None. There is no supplement combination that makes bloodroot safe or useful, and nothing should be stacked with it.

Two documented synergies are worth knowing because they explain product design rather than recommend it.

• Zinc. Eisenberg and colleagues showed sanguinarine and zinc act synergistically against oral streptococci and actinomyces, which is why every sanguinaria oral care formula paired the extract with zinc chloride. In the escharotic pastes the same pairing serves a different purpose, since zinc chloride is itself a tissue fixative. The synergy in a salve is a synergy of destruction.

• DMSO. Some black salve formulations add dimethyl sulfoxide as a penetration enhancer. This is not a benefit. It increases the depth to which a caustic reaches.

Interactions & What NOT to Take

Digoxin and other cardiac glycosides

Sanguinarine inhibits Na+/K+-ATPase at 6.0 to 6.5 micromolar, the same pump digoxin targets. Additive inhibition is a plausible mechanism for arrhythmia. Avoid combination.

Anticoagulants and antiplatelet drugs, including warfarin, apixaban, clopidogrel and aspirin

Not a pharmacokinetic interaction but a practical one. A topical escharotic produces an open, eroding wound that can bleed arterially, as the 86-year-old with the temple hemorrhage demonstrated. Anticoagulation turns that from a wound into an emergency.

Any conventional skin cancer treatment

Do not use black salve before, during or instead of surgery, imiquimod, 5-fluorouracil, cryotherapy, radiotherapy or photodynamic therapy. The specific harm is that the salve destroys the lesion's architecture and margins, so a later biopsy of the scarred site may not represent the tumor that was there, which is exactly what happened in the Bozung periorbital case where residual carcinoma was found buried in cicatricial tissue.

Immunosuppressants, including tacrolimus, ciclosporin, mycophenolate and post-transplant regimens

Transplant recipients have sharply elevated squamous cell carcinoma risk and impaired wound healing. An escharotic burn in this population is a poor idea on both counts.

What to tell a clinician

Disclose salve use explicitly. It is not visible on a pathology slide as "black salve," it presents as necrosis with implanted foreign material and reactive stromal atypia that can be misread. Leecy's series made exactly this point to pathologists.

Quality, Testing & Adulteration

This is the section where bloodroot is worse than almost anything else on the shelf, because there is no meaningful quality infrastructure for it at all.

No pharmacopoeial monograph in routine use, no marker assay on labels

No consumer bloodroot capsule, tincture or salve reviewed declares sanguinarine or chelerythrine content. Since the rhizome ranges from 0.6 to 6.3 percent sanguinarine by dry weight with 15-fold variation between individual rhizomes, a label declaring milligrams of root declares almost nothing about milligrams of active. This is not a subtle standardization gap. It is a tenfold uncertainty in an alkaloid with a low emetic threshold.

Wildcrafted material dominates, and it is the more variable material

United Plant Savers lists Sanguinaria canadensis on its Species At-Risk list, notes that nearly all commercial bloodroot is wild harvested, and cites estimates of roughly 38 to 55 tons of annual wild harvest, with one report of 135,000 pounds sold into the trade in 2001. It is listed as Exploitably Vulnerable in New York and of Special Concern in Rhode Island. Graf's comparison of wildcrafted and cultivated rhizome found wild material higher in alkaloid but markedly more variable, which is the worst combination for a product with no assay.

Third-party certification is effectively absent

There is no USP Verified bloodroot ingredient, no NSF Certified for Sport bloodroot product, and no meaningful ConsumerLab category. A certificate of analysis for a bloodroot product should show, at minimum, botanical identity confirmation to Sanguinaria canadensis by HPTLC or DNA barcode, quantified sanguinarine and chelerythrine by HPLC, heavy metals, microbial limits and residual solvent for extracts. In practice buyers are handed none of this.

Species substitution is a live risk in this family

Macleaya cordata and Chelidonium majus both contain sanguinarine and chelerythrine, and Macleaya is the commercial sanguinarine source for the feed industry. Argemone mexicana, the source of the argemone oil behind epidemic dropsy, is another sanguinarine-bearing Papaveraceae. A botanical ID claim of "bloodroot" backed by an alkaloid fingerprint alone cannot distinguish these, because the fingerprint is shared. Identity here requires morphological or genetic confirmation, not chemistry.

The salve category has no composition at all

The published reviews describe black salve as having no standard formula, with wide variation between makers in bloodroot content, zinc chloride content and added botanicals. FDA's Haloderm letter and Healing Within letter both proceeded on unapproved-drug and misbranding grounds rather than composition, because there is no declared composition to contest. Konkel's FDA pharmacovigilance series found 7 of 38 injury cases involved products with no ingredient list whatsoever.

What a buyer can actually verify

For the escharotic products, nothing, and the correct action is not to buy them. For oral products, a buyer can verify Latin binomial on the label, a lot number, a contactable manufacturer and whether an HPLC alkaloid assay is offered on request. If sanguinarine is not quantified, the product is unquantified by definition.

Special Considerations

Pregnancy, breastfeeding, children, renal or hepatic impairment

Avoid entirely. Documented emmenagogue and uterine-stimulant activity with no safety data, a caustic paste that is a pediatric emergency risk in the home, and no characterization of sanguinarine disposition in impaired clearance.

Prior Viadent users

Anyone who used the sanguinaria dentifrice or rinse regularly before the 2001 reformulation should mention it at dental examinations. Ohio State University's dental faculty publicized this in December 2001 because the lesions were still turning up years after exposure ended.

People choosing alternatives to surgery out of fear

This is the population the case literature is actually about, and the response that works is not a lecture about pseudoscience. Worley's report concluded that reconciling the patient's preference for natural remedies with effective oncological treatment is the communication problem to solve. The relevant facts are that Mohs surgery on the face has five-year recurrence rates around 1 percent, is done under local anesthetic, and preserves more tissue than any other method precisely because the margin is read as it goes.

Regulatory position by jurisdiction

The FDA advisory of 13 October 2020 tells consumers not to use products containing sanguinarine, Sanguinaria canadensis or bloodroot, alone or with zinc chloride, for any skin condition. Australia's Therapeutic Goods Administration has warned against purchase and use, and New Zealand's Medsafe issued a "Black Salve, Buyer Beware" alert in 2013. Australia's most severe case involved the 2018 death of Helen Lawson after black salve application under the direction of a self-described healer, Dennis Wayne Jensen, who received a prohibition order from Victoria's Health Complaints Commissioner.

The prosecution

Greg Caton founded Alpha Omega Labs in 1995 and sold Cansema as a skin cancer cure. He was convicted in May 2004 in federal court in Louisiana on charges including mail fraud and introduction of unapproved new drugs into interstate commerce, and in August 2004 was sentenced to 33 months in prison followed by three years of supervised release, with forfeiture of two buildings and his residence in Lake Charles. The scheme was documented as running from 1999 to 2003 and generating approximately $950,000. He relocated to Ecuador in violation of supervised release, was arrested there in early December 2009, deported to the United States, and in May 2010 was ordered to serve the remainder of his term in prison. An appeal was denied on 23 June 2011. He resumed selling online from Ecuador and died there in December 2021. Cansema is still available.

Research Status & Evidence Quality

Strong Evidence For

• Sanguinarine is a potent, non-selective cytotoxin in vitro. 24-hour half-maximal inhibitory concentrations of 2.1 micromolar (A375 melanoma) and 3.14 micromolar (A431 squamous cell carcinoma), more cytotoxic than 5-fluorouracil at 24 hours, with the review authors' own conclusion being that this implies normal tissue toxicity.

• Topical bloodroot plus zinc chloride causes tissue necrosis, scarring and disfigurement in humans, documented across dozens of case reports from at least six countries and in an FDA pharmacovigilance series.

• Black salve does not reliably clear skin cancer, and it is not tumor-specific. Croaker's national Australian series covered 409 patients and 475 lesions, and specimen numbers more than doubled from 2015 to 2019 despite regulatory warnings.

• Chronic sanguinaria oral care use is associated with leukoplakia of the maxillary vestibule. Damm and colleagues (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;87(1):61-66) reviewed 88 patients with maxillary vestibular leukoplakia and found 84.1 percent reported Viadent use against 3 percent in 100 randomly selected adults. Allen's accompanying editorial in the same volume (87(4):393-394) asked whether it was the tip of the iceberg. Mascarenhas, Allen and Loudon (Epidemiology 2001;12(6):741-743) ran 148 cases and controls and reported an adjusted odds ratio of 9.7 (95 percent CI 4.7 to 21.6) with a dose-response relation. Mascarenhas, Allen and Moeschberger (J Public Health Dent 2002;62(3):158-162) then ran 58 matched pairs and reported an odds ratio of 10.0 (95 percent CI 2.0 to 89.2). Bloodroot was removed from the formula in 2001 and the brand subsequently left the market.

Moderate Evidence For

• Sanguinaria-associated keratosis carries histological features intermediate between normal mucosa and dysplasia. Eversole, Eversole and Kopcik (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;89(4):455-464) found significantly elevated proliferating cell nuclear antigen labeling without significant p53 expression, and 1.5 percent of the epithelial cell population carrying nuclei with more than a four-fold increase in DNA content. Anderson and colleagues (Oral Oncol 2005;41(2):200-207) found p53 staining at 2.65 in normal mucosa, 4.64 in Viadent-associated lesions and 8.71 in dysplasia, concluding the profile supports a preneoplastic process.

• Sanguinaria dentifrice plus rinse reduced plaque and gingivitis in six-month company trials. Harper 1990, n=60, 21 percent lower plaque, 25 percent lower gingivitis and 43 percent lower bleeding on probing at 28 weeks. Independent single-agent testing was negative, which is why this sits at moderate rather than strong.

Emerging / Preliminary Evidence For

• Sanguinarine as a telomerase inhibitor and ferroptosis inducer in cancer models. Cell culture only. No human data. These findings do not transfer to a salve.

• Carcinogenic potential of sanguinarine itself. Contradictory genotoxicity and rodent carcinogenesis results, an unresolved question rather than a reassurance.

• Theoretical risk of epidemic dropsy features from black salve, raised on the basis that salve sanguinarine concentrations exceed those in the argemone-contaminated massage oils that have caused dropsy transdermally. Not observed clinically to date.

Research Limitations

There has never been a randomized controlled trial of black salve for any skin condition. There has never been a randomized controlled trial of oral bloodroot for any respiratory condition. Every efficacy claim made for the escharotic use rests on in-vitro cytotoxicity plus vendor testimonial, and the structural obstacle to ever fixing this is the one described at the top of this issue: the intervention destroys the specimen. Even a trial that wanted to measure clearance would have no margin to read and no baseline histology surviving. Meanwhile the pharmacovigilance data, which does exist, points one way. FDA logged 24 adverse event cases for black salve with at least one death, and 38 serious skin injuries from mole and tag removers containing Sanguinaria canadensis and other caustics, 28 of them in 2021 alone.

Summary & Key Takeaways

Bloodroot is a real plant with real pharmacology and a hundred and seventy years of commercial history built almost entirely on one property: it destroys tissue. The oral care industry took the same molecule, diluted it to 0.075 percent in toothpaste and 0.03 percent in rinse, discovered it reduced plaque, sold it from 1983, and then quietly removed it in 2001 after four independent research groups linked it to leukoplakia of the maxillary vestibule with odds ratios near 10. The escharotic industry never diluted it, never removed it, and is still selling it.

Bottom Line

Do not put bloodroot on your skin. There is no lesion for which a self-applied caustic is the right treatment, and the specific danger is not that black salve fails to burn but that it burns successfully while leaving no way to know what it burned. Oral bloodroot has no controlled human evidence for any indication, a low emetic threshold and a digoxin-like action on the sodium pump, sold in capsules whose alkaloid content can vary tenfold between lots because nobody assays it.

Key Safety Points

• Any suspicious skin lesion needs a biopsy, not a paste. Mohs surgery clears basal cell carcinoma with five-year recurrence rates around 1 percent and reads the margin as it goes.

• Stop immediately if a salve has been applied and take the packaging to a clinician. Report to FDA MedWatch at 1-800-332-1088.

• Avoid in pregnancy, breastfeeding, childhood, and alongside digoxin or anticoagulants.

• A white patch in the upper labial vestibule with a history of sanguinaria oral care products warrants examination and, if persistent, biopsy.

• No product on this shelf declares sanguinarine content. Treat any milligram figure on a bloodroot label as a weight of plant, not a dose of drug.

Special Note

The lesson here generalizes past bloodroot. When a product's marketing offers you a visible sign that it is working, ask whether that sign is the mechanism or the damage. With black salve the two are the same event: the plug that falls out is presented as the tumor leaving and is in fact the tissue that died. Any therapy that destroys its own evidence is unfalsifiable by design, and unfalsifiable is not the same as effective. Cell-culture cytotoxicity is where this pattern usually starts, so carry one more rule with you. Before accepting a laboratory kill as a reason to buy something, ask what else the compound kills. If the answer is everything, the assay measured the wrong thing.