Black salve is a corrosive paste promoted as an alternative treatment for skin cancer, moles, and other skin lesions, but the medical evidence overwhelmingly shows it is unsafe and ineffective. The paste destroys tissue indiscriminately, often leaves cancer behind, and can cause disfiguring wounds that require hospitalization. Despite decades of warnings from medical professionals and regulatory agencies, black salve products continue to circulate online and through alternative health networks, making it worth understanding exactly what this substance is, what it does to the body, and why mainstream medicine considers it dangerous.
What Black Salve Contains
Black salve is not a single standardized product. It is a category of paste-like preparations that share two key active ingredients: extracts from the rhizome of bloodroot (Sanguinaria canadensis), a flowering plant native to North America, and zinc chloride, a caustic chemical salt.1Journal of Herbal Medicine. Black salve composition: An evaluation of the potential for normal tissue toxicity and treatment failure from black salve products Either ingredient alone can burn through living tissue. Together, they form an escharotic agent, meaning a substance that creates a thick, dark scab called an eschar by chemically destroying the tissue it contacts. Various formulations add other herbal extracts, waxes, or carrier substances, but bloodroot and zinc chloride are what give black salve its corrosive properties.2PubMed. A review of topical corrosive black salve
Because black salve is sold outside regulated pharmaceutical channels, there is no quality control over what goes into any given batch. Concentrations of zinc chloride and bloodroot vary widely between products and even between batches from the same seller. A person buying black salve online has essentially no way of knowing how concentrated or how corrosive the paste they receive will be.
What People Use It For
The primary promoted use of black salve is treating skin cancer, particularly basal cell carcinoma, squamous cell carcinoma, and melanoma. Sellers and proponents claim it selectively destroys cancer cells while leaving healthy tissue intact. This claim is the central selling point and, as we will see, the central falsehood. Beyond cancer, some people apply black salve to moles, skin tags, cysts, warts, and other benign growths they want removed. In one published case, a patient applied a commercially branded black salve product (Two Feathers Healing Ointment) to a cyst and kept it in contact with his skin for seven days, resulting in a wound that required oral antibiotics and referral to a wound care clinic.3PubMed Central. Black salve: risky escharotic
The appeal is understandable at a human level. Skin cancer diagnosis is frightening, surgical removal leaves scars, and the idea of a simple topical paste that “draws out” cancer feels empowering. Online communities share dramatic photographs of black eschars falling off to reveal what looks like healed skin, framing this as evidence the product works. What those photographs do not show is what is happening under the surface.
Why Black Salve Does Not Selectively Target Cancer
The claim that black salve kills cancer cells while sparing healthy tissue has been examined directly, and the evidence runs in the opposite direction. A detailed review analyzing the cytotoxicity of black salve’s ingredients, post-treatment tissue samples, and comparisons to clinical zinc chloride paste (Mohs paste, used in a now-outdated surgical technique) concluded that black salve is likely toxic to normal tissue, and that some cancer cell lines may actually be relatively resistant to its effects.4PubMed Central. A Review of Black Salve: Cancer Specificity, Cure, and Cosmesis In other words, the selectivity claim is not just unsupported; the available data suggest the truth may be the reverse. Healthy skin cells get destroyed while some cancer cells survive.
This makes biological sense when you think about what black salve actually is. It is a chemical burn agent. Zinc chloride dissolves proteins on contact. Bloodroot contains alkaloids that disrupt cell membranes. Neither substance has any mechanism for distinguishing a cancer cell from a normal skin cell. When applied to the skin, the paste burns through everything it touches, creating a crater of dead tissue. The resulting eschar (the dark, hard scab) looks dramatic and can feel like proof that something pathological has been removed. But pathological examination of the tissue beneath these eschars frequently reveals a different story.
How Often Cancer Persists After Black Salve Treatment
The largest study to date on black salve outcomes examined Australian pathology specimens collected over five years. During that period, 409 patients treated 475 skin lesions with black salve. Of those lesions, about 18% turned out to be benign, meaning those patients burned their skin with a corrosive agent for no medical reason at all. Among the remaining lesions that were actually cancerous, persisting cancer was found in over a third of cases.5PubMed Central. Persisting Cancer in Black Salve Treated Skin Lesions: Results of a Large 5 Year Retrospective Analysis of Australian Histopathology Specimens
That number deserves emphasis. More than one in three cancerous lesions treated with black salve still had cancer present when later examined by a pathologist. The surface may have looked healed. The eschar may have fallen off. The patient may have believed the cancer was gone. But the malignant cells were still there, potentially growing deeper into the tissue where they are harder to detect and harder to treat. This is the core danger: black salve creates the appearance of cure while often leaving the disease in place.
Documented Cases of Serious Harm
Published case reports illustrate what can go wrong when black salve is used instead of proven treatments. In one case, a woman diagnosed with superficial spreading melanoma chose to treat it with black salve rather than undergo surgical excision. The melanoma persisted, and five years later it had metastasized to her lymph nodes, lungs, liver, subcutaneous tissues, and muscle.6PubMed Central. Application of black salve to a thin melanoma that subsequently progressed to metastatic melanoma: a case study A thin, early-stage melanoma that could likely have been cured with straightforward surgery became a widely disseminated cancer. The window for curative treatment closed while the patient believed black salve was working.
A separate case reported a patient with melanoma in situ who self-treated with black salve and ended up hospitalized with extensive tissue damage.7PubMed Central. A case of compound X (black salve) self-treated melanoma in situ leading to hospitalization and extensive tissue damage In another, a patient with a nasal basal cell carcinoma used an escharotic agent and the lesion appeared to heal for several years before recurring deeply, requiring extensive surgical resection. That cancer eventually metastasized.8PubMed. Consequences of using escharotic agents as primary treatment for nonmelanoma skin cancer These are not freak occurrences. They represent a pattern: black salve destroys the visible surface layer of a lesion, creating the illusion of treatment, while cancer cells deeper in the skin survive and continue to grow undetected.
The Problem Black Salve Creates for Diagnosis
Even when patients eventually seek conventional medical care after using black salve, the damage it causes creates new problems. A series examining 16 pathology specimens from black salve-treated skin found that the escharotic destruction created a range of unusual tissue changes that can confuse histopathological diagnosis. Dermatologists and pathologists reviewing these specimens noted poor cosmetic outcomes and cases where malignant tumors were effectively masked by the uncontrolled tissue destruction.9PubMed. Histopathological features associated with application of black salve to cutaneous lesions: a series of 16 cases and review of the literature
This is a less obvious but clinically significant harm. After black salve treatment, the tissue architecture that pathologists rely on to determine tumor type, depth, and margin status has been scrambled. It becomes harder to tell whether cancer cells remain, how deep they extended, and what kind of follow-up treatment is needed. The chemical burn essentially destroys the evidence that doctors need to make good decisions. Patients who turn to conventional medicine after black salve may face more aggressive treatment than they would have needed originally, precisely because the diagnostic picture has been muddied.
The Mohs Surgery Connection
One historical fact sometimes used to lend credibility to black salve is that zinc chloride paste was once central to legitimate cancer surgery. This is true but misleading. In the 1930s, Dr. Frederic E. Mohs developed a surgical technique called chemosurgery, which used zinc chloride paste to fix tissue in place before removing it layer by layer under microscopic examination. The technique achieved high cure rates, but it was slow, sometimes taking days to complete, and it gradually gave way to the fresh tissue technique now known as Mohs micrographic surgery, which uses no chemical paste at all.10PubMed Central. History of Mohs surgery
The critical difference between Mohs’ original chemosurgery and self-applied black salve is that Mohs used zinc chloride as one step in a tightly controlled surgical process where every layer of tissue was examined under a microscope to verify whether cancer cells remained. The paste was never the treatment by itself. It was a tool used by a trained surgeon alongside real-time pathological analysis. Black salve used at home, by contrast, involves applying a corrosive chemical with no diagnostic feedback whatsoever. Nobody is checking whether the cancer has been fully removed. Nobody is examining margins. The patient is simply hoping the paste burned deep enough and wide enough, which, as the Australian data showed, it frequently does not.
Regulatory Warnings and Ongoing Availability
Government agencies have issued clear warnings against black salve. The U.S. Food and Drug Administration has listed black salve products among fake cancer cures, and the Australian Therapeutic Goods Administration has taken action against sellers. Medical literature consistently describes black salve as a dangerous compound that has persisted as an alternative treatment despite these warnings.11PubMed Central. Black Salve: A Dangerous Corrosive Disguised as an Alternative Medicine
Despite regulatory efforts, black salve remains easy to obtain. Products are sold under various names, with marketing language that avoids explicit cancer treatment claims while strongly implying them. Terms like “drawing salve,” “healing ointment,” and references to Native American or herbal traditions are common. Online forums and social media groups share instructions for making black salve at home from raw bloodroot and zinc chloride. The decentralized nature of internet commerce makes enforcement difficult, and the products tend to resurface under new names after any particular brand is shut down.
What Proven Treatments Look Like
For the types of skin cancer and precancerous lesions that people most commonly try to treat with black salve, evidence-based options are well established and have high success rates. Surgical excision and Mohs surgery remain the gold standard for most basal cell and squamous cell carcinomas, with cure rates above 95% for primary tumors. For melanoma, early surgical excision is critical and remains the single most effective intervention.
Topical treatments also exist for certain early or superficial lesions. Imiquimod, for instance, is an immune-modulating cream approved for treating actinic keratoses (precancerous sun-damage spots), superficial basal cell carcinomas, and external genital warts.12PubMed Central. Safety, efficacy, and patient acceptability of imiquimod for topical treatment of actinic keratoses Unlike black salve, imiquimod works by stimulating the body’s own immune response against abnormal cells, it has been tested in clinical trials, and it is used under medical supervision with pathological follow-up. Other options for superficial lesions include fluorouracil cream, photodynamic therapy, cryotherapy, and curettage with electrodesiccation. The point is not that any one treatment is perfect but that all of these have been studied, have known success and failure rates, and are administered within a system that verifies whether the cancer has actually been eliminated.
Veterinary Use of Bloodroot Preparations
An interesting corner of this topic involves the use of bloodroot-based preparations in veterinary medicine, specifically for equine sarcoids, a common skin tumor in horses caused by bovine papillomavirus. A retrospective survey of horse owners whose animals were treated with a bloodroot ointment (sometimes called Newmarket bloodroot ointment in the UK) found that of 74 sarcoids in 49 horses, 49 responded completely and 15 partially, while 10 did not respond or worsened. Smaller sarcoids (under 2 cm) responded significantly better than larger ones.13PubMed Central. Owners’ perception of the efficacy of Newmarket bloodroot ointment in treating equine sarcoids
This might sound like vindication for black salve, but the context matters. Equine sarcoids are locally invasive tumors that rarely metastasize, so the stakes of incomplete removal are very different from those in human skin cancer. Veterinary use also typically occurs under a veterinarian’s guidance, with the ability to monitor the wound and intervene if the treatment fails. And even in this veterinary setting, researchers have raised concerns that so-called “herbal” preparations for equine tumors may contain significant amounts of zinc chloride without labeling it clearly, meaning veterinarians and horse owners may not realize they are applying a caustic chemical.14Equine Veterinary Education. ‘Herbal’ preparations for equine dermal neoplasms contain large amounts of zinc chloride The veterinary literature on bloodroot ointments is more nuanced than the human literature, but it does not support generalizing those results to human cancer treatment.
Why People Still Use It
Given all of this evidence, the persistence of black salve use can seem baffling from the outside. Several factors help explain it. The visual drama of the eschar is powerful. When a thick black scab forms and eventually falls off, it genuinely looks like something has been pulled out of the body. Confirmation bias does the rest: if the surface heals over, the patient concludes the cancer is gone, and unless they get a follow-up biopsy (which black salve proponents often discourage), they may never learn it was not. Some of those patients then share their apparent success stories online, creating a feedback loop of anecdotal evidence that drowns out medical warnings.
Cost and access play a role too. In countries without universal healthcare, skin cancer treatment can be expensive, and the gap between diagnosis and surgery can feel long and anxious. A $30 jar of paste that promises immediate action fills that emotional gap even when it fails medically. Distrust of the medical system, fueled by real experiences of being dismissed or overcharged, also pushes some patients toward treatments they can control themselves. Understanding these motivations does not change the medical reality, but it is worth recognizing that the appeal of black salve is not purely irrational. It exploits real vulnerabilities in how people experience healthcare.
For anyone who has already used black salve on a skin lesion, the most important step is getting a proper medical evaluation, including a biopsy of the treatment site if possible. The surface appearance of healing does not reliably indicate whether cancer cells have been eliminated. Given that more than a third of cancerous lesions in the Australian study still harbored cancer after black salve treatment, assuming the worst and seeking follow-up is the safest course.5PubMed Central. Persisting Cancer in Black Salve Treated Skin Lesions: Results of a Large 5 Year Retrospective Analysis of Australian Histopathology Specimens