Jun 21 2013

Black Salve is Quackery

I received this question from an SGU listener:

I’ve been listening to your show for years now, thanks for brightening my life. 🙂
I have a question about an alternative cancer treatment my mother has started using to treat ‘skin cancer’ on her face (undiagnosed). It is called Black Salve and people claim it removes the cancerous cells from your flesh without damaging healthy cells. The ‘cancer’ literally falls out of your skin.
Do you know anything about this? What is your view on this treatment?

Thanks again for a great show.

I get similar questions almost every day. There appears to be an endless supply of dubious health claims and products – far more than any one person can deal with, with new ones popping up so fast it is a losing game of whack-a-mole. This is why I strongly advocate more effective regulation.

(warning: graphic picture below the fold)

Meanwhile, my colleagues and I are trying to develop resources on the internet to combat the steady flow of medical nonsense. While that is in the works, there are some existing resource, like the Science-Based Medicine website. There is also QuackWatch, run by Stephen Barrett. He has spent years writing and editing articles, and by now most topics are covered fairly well on the site.

QuackWatch has an excellent article on Black Salves, which I suggest you simply read in its entirety. I will add some additional resources.

The bottom line is that Black Salve is a general name for a topical ointment that is corrosive and is used to burn away skin lesions, including cancer. There are no proper scientific studies of its safety and efficacy, and the exact ingredients are formulas vary and are often not known.

The idea that such corrosives kill cancer cells but do not harm healthy skin cells is false. There is not justification for this claim. The notion that such ointments draw out cancer cells or cause them to “fall out of the skin” is beyond false – it’s absurd.

Self-treatment for skin cancer or lesions with such salves is likely to cause unnecessary damage to healthy tissue. Dr. Barrett includes some example, and here is another from a recently published study (sorry, it may be behind a paywall). It documents the case of a patient who burned half his nose away with a black salve. I apologize for the picture, but it’s important for people to see what we are talking about, and most people will not be able to access this article.

Further – such self-treatment is completely unnecessary. Skin cancers are almost 100% curable with modern treatments, which are designed to minimize any scarring. Here we have a case of a condition that is successfully treated with modern medicine, and yet some people are opting for outdated treatments that may not be effective and cause significant harm.

Such unfortunate decisions are promoted by advocates of black salve, who either are selling a product or seem to have a certain ideological position. Unsurprisingly, NaturalNews is promoting “Indian Black Salve” as a “magical cancer cure.” This salve contains bloodroot, which is used as a corrosive agent. Of course, they claim it targets cancer cells while leaving healthy cells alone (false), they promote it with the naturalistic fallacy, and they claim it is rejected by the FDA and mainstream doctors because it is all natural and cannot be patented. All absurd claims.

The only good advice is to stay completely away from black salve. Avail yourself of modern medicine if you have a suspicious skin lesion or known skin cancer.

20 responses so far

20 thoughts on “Black Salve is Quackery”

  1. “… with new ones popping up so fast it is a losing game of whack-a-mole. ”

    I propose a new name for the pastime: “quack-a-mole” Or perhaps “whack-a-quack”?

  2. ConspicuousCarl says:

    Black salve is an interesting thing to consider next to homeopathy because each is at one extreme of uselessness. One of those those things does absolutely nothing, the other is completely destructive. But in both cases, pure mental acrobatics convinces people that they have some special fine-tuned selective instrument of healing.

  3. HHC says:

    Do you have a picture of this patient after traditional dermatology or reconstructive surgical intervention?

  4. Orac says:

    Black salve is nothing more than, as I put it, “cutting, poisoning, and burning naturally”:


  5. tompocket says:

    I read the entire article thinking it was called black slave…

  6. Bronze Dog says:


    That’s made from avacados, right?

  7. tmac57 says:

    Too bad that critical thinking skills are not “all natural”…gullibility on the other hand…

  8. NNM says:

    Dr Novella,
    Science is often hidden behind these “paywalls”, as you called it.
    It’s very annoying. “Quack” claims are always free and easily accessible.
    I love to learn things on my own, and study various topics in my free time; but I do believe knowledge should be free, and am often hindered by these paywalls.
    If knowledge was free, there would be less people falling for all these “quackeries”, and our civilization would advance much faster. Idiotic “theories” like creationism would become instinct, instead of being a real threat to education (American example).
    (It was really painful to call it a “theory”, even with quotes.)
    If you really want to make a change, then making knowledge free and more accessible would be the most efficient tactic, rather than a blog, read mostly by science nerds (and some disturbing people who seem to write more in the comments than your entries at times…).
    I see quack claims like this everywhere. I’ve seen many very rational people fall to these dangerous quackeries. Cancer makes people desperate.
    – “Well, it can’t hurt to try?” – “Yes, It can.”
    I’ve had to stop people from ingesting poisonous substances, and gathering convincing REAL material was very hard.

  9. NNM says:

    Sorry, double post, need to add an example:
    A group of people close to me are taking this daily, and started ingesting excessive amounts of https://en.wikipedia.org/wiki/Apricot_kernel.
    Some of them still consume such products daily, and suffer.
    Is this going to lead me to convincing material:
    Even less!

  10. BillyJoe7 says:


    “If you really want to make a change, then making knowledge free and more accessible would be the most efficient tactic, rather than a blog, read mostly by science nerds”

    How do you know this blog isn’t making a change.
    The readers here are probably passing on information obtained here to others in their circle producing an amplifying effect.
    How do you know SN isn’t also working on making knowledge free and more accessible?
    And why do you think it’s a good idea for everyone to concentrate on one thing to the exclusion of everything else.
    Besides, SN may also regard this as an interesting pastime.
    Should I stop my Sunday morning hill runs so I can concentrate on learning and imparting as much science and as I can?

  11. NNM says:

    It wasn’t meant as an attack on Dr. Novella, nor on his blog.
    I have many ideas on how we can fix the situation.
    My above searches highlight the real problem: anyone searching for the above information is not going to find scientific views, but will mainly find websites trying to sell or promote these quackeries.

    I used duckduckgo because I know everyone will get the same results, rather then results based on previous searches and interests. (Also, because it’s better and probably the search engine that I think will dominate the future.)
    But that also means anyone with an interest in healing and things like that will probably never encounter a website contradicting their beliefs, and see more ads promoting the quackeries….
    This actually makes websites such as google, bing, yahoo (& co) enemies of knowledge and just as guilty as quacks. Sadly, duckduckgo is also guilty: they also get paid by these websites every time someone buys something from amazon, for example. I’m not making this up, I’ve actually talked to them about it, and yes, they do get money every time someone buys something from amazon after a search; so searching
    I have several ideas on how to fix this, but I could never accomplish this alone.
    One of them: the world needs a new, BIG, non profit, search engine.
    Hint for free massive hosting solution: seti@home.
    Hint for getting many programmers: Mozilla.
    Hint for public “ambassador”: Dr Novella.
    Hint for incorruptible CEO/head programmer: ME!? ;oP
    Yes, it’s a long shot, but my dream.

  12. Bruce Woodward says:

    “My above searches highlight the real problem: anyone searching for the above information is not going to find scientific views, but will mainly find websites trying to sell or promote these quackeries.”

    I find this too. It is so hard to filter through information on the internet and unless you really know the red flags and understand what real evidence looks like you have a hell of a problem sometimes finding real information on any number of issues.

    Simple things like using the wrong keywords in your search can pull you down the wrong alley very easily.

  13. NNM says:

    So we need a new search engine.
    One that excludes all websites selling items (amazon, ebay, etc domains blacklisted).
    One that only provides information.
    Possibly, one that attempts to filter out misinformation.
    A true information database, with no agenda other than spread knowledge.
    It will be the start page for all students.
    google&co have become rotten to the core and their primary goal has NEVER been information, but REVENUE.
    I have a dream….

  14. Sherrington says:

    I often search for primary source research articles and have found several approaches to use when facing a paywall.

    First of all, not all journals have paywalls — PLOS (Public Library of Science) articles are always freely available. Many articles at PNAS (Proceedings of the National Academy Sciences) are as well.

    Second, if I have the title of the article (such as from the abstract), I search for it at Google Scholar, with the title in quotes. This will show the various sources for this article and if a pdf is available. Sometimes researchers have a website with links to their articles, and this may show up at Google Scholar.

    Third, if it is a recent article, I will email the corresponding author. The address can usually be found at the website for the journal — the same place where you usually find the paywall. I have had good success at getting pdfs this way. I should add that I do work at a college and so I am not sure if having an “edu” as part of my email address makes them more likely to respond.

    Finally, I mentioned using Google Scholar to search for a specific article. It can also be used as a research tool using key words, although it has limitations compared to databases such as PubMed, for example. But, one advantage is that you can clearly see in the search results if there is a pdf available. Just for kicks, I searched for “black salve” there and found a negative article on the treatment from THE JOURNAL OF ALTERNATIVE AND COMPLEMENTARY MEDICINE:


  15. “A true information database, with no agenda other than spread knowledge.”


  16. ConspicuousCarl says:

    NNM on 23 Jun 2013 at 7:03 am
    So we need a new search engine.
    One that excludes all websites selling items (amazon, ebay, etc domains blacklisted).

    What if someone is trying to find a place to buy something?

    And how much of a problem is it? I am not overloaded with Amazon links when I search for trials of new drugs.

  17. ConspicuousCarl says:

    I am pretty sure this has been addressed before…

    Yes, it is annoying when people like us are curious to know some specific details in a paper, but I don’t think that the sort of people who are typically duped by homeopathy are going to benefit much from reading research papers. In fact, you could do a good job of duping people just by selectively referring them to poorly-designed studies which have been published.

    As Ori said, Wikipedia is made to give the entire population access to well-written information which represents a subject accurately based on clear citations. It’s not always perfect, but it is very close on major issues.

  18. Bruce Woodward says:

    Ah, that small amount of inaccuracy is thrown back in my face every time I quote wikipedia… and even snopes is now being said to be inaccurate.

    As soon as a site goes against their beliefs it is suddenly not reliable, and if there is a known percentage of inaccuracy, people will quote that as it being inaccurate for their specific issue.

    As Carl said, access to the data does not mean people will change their beliefs in most cases.

  19. edamame says:

    While I am not promoting its use by laypeople, I can understand how people have (mistakenly) taken some strands of the scientific literature (which does examine “black salve” ingredients, in particular blood root extract) and gone this route. It is actively being explored by cancer researchers:

    Aburai, Nobuhiro; Yoshida, Mami; Ohnishi, Motoko; Kimura, Ken-Ichi (2010). “Sanguinarine as a Potent and Specific Inhibitor of Protein Phosphatase 2C in Vitro and Induces Apoptosis via Phosphorylation of p38 in HL60 Cells”. Bioscience, Biotechnology, and Biochemistry 74 (3): 548–52.

    Ahmad, Nihal; Gupta, Sanjay; Husain, Mirza M.; Heiskanen, Kaisa M.; Mukhtar, Hasan (2000). “Differential Antiproliferative and Apoptotic Response of Sanguinarine for Cancer Cells versus Normal Cells”. Clinical Cancer Research 6 (4): 1524–8.

    Sun, Meng; Lou, Wei; Chun, Jae Yeon; Cho, Daniel S.; Nadiminty, Nagalakshmi; Evans, Christopher P. et al. (2010). “Sanguinarine Suppresses Prostate Tumor Growth and Inhibits Survivin Expression”. Genes & Cancer 1 (3): 283–92.

    Frankly, if we were talking about inoperable, incurable cancer here, and we saw these results, I might consider bloodroot as a desperation shot that could be better than nothing. But we are not, and its use is unjustified in the form it is presently being used. As argued here by Dr Novella and this old article:
    McDaniel, S.; Goldman, GD (2002). “Consequences of Using Escharotic Agents as Primary Treatment for Nonmelanoma Skin Cancer”. Archives of Dermatology 138 (12): 1593–6.

    Though admittedly, this review came out before the above articles, so it is a bit out of date.

    Note I got these references from Wikipedia on bloodroot.

  20. NNM says:

    “What if someone is trying to find a place to buy something?”
    ..Then don’t use “my” search engine. That’s not the purpose. Then you can go to google.

    “access to the data does not mean people will change their beliefs in most cases.”
    .. That’s not the purpose either. If you wanted to find testimonials on how black salve (example) works, you’d find it as well. You just wouldn’t find anyone selling it.

    Not a search engine. A minimalistic encyclopedia… Even dangerous! as some people tend to think “well, look that’s what wikipedia says”…

    No, I’m thinking of a real internet search engine, without ads, no sellers, no social media, etc… Non profit.. Free, open. Something where indexing somewhat reflects scientific consensus.
    The “big” thing would be indexing research studies, reviews, scientific blogs, a bit of everything, just cleaned up of all garbage, while keeping it open to all views.. Wikipedia would probably be in top results most of the time. But BS results such as amazon.com?search=black&20… GONE.
    Hosted on a p2p network, where volunteers would run a desktop client such as seti@home, and get virtual “credits” for number of searches served, number of pages indexed, etc..

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