Homeopathic Insect Repellent: Is there anything the Natural Health Products Directorate won’t approve?

A recurring focus of this blog has been to examine the implications and consequences of the uniquely Canadian approach to  regulating the consumer market for what are termed “natural health products”. One of the triumphs of the Canadian natural product and supplement industry was the 1990′s decision to create different regulatory standards for the evaluation and approval of these”non-drug” products. The Natural Health Product Regulations, under Canada’s Food and Drugs Act, regulate products such as nutritional supplements, probiotics, traditional Chinese medicine, vitamins, herbal remedies, and homeopathy. They are a deliberate shadow of the regulations that govern drug products — requiring some manufacturing quality and safety standards, while effectively removing the standards for product efficacy claims. Standards were dropped because there was no possible way that many of these products could ever meet the rigorous standards established for drug products. The most problematic in the group was homeopathy. Homeopathy is an elaborate placebo system, where the “remedies” lack active ingredients. As would be expected with inert products, clinical trials confirm what basic science predicts: homeopathy’s effects are placebo effects. Yet Health Canada insists that this doesn’t compromise quality, safety, or efficacy:

Through the Natural Health Products Directorate, Health Canada ensures that all Canadians have ready access to natural health products that are safe, effective and of high quality, while respecting freedom of choice and philosophical and cultural diversity.

The consequence? Regulation of the absurd. Health Canada reviews every remedy, and explicitly attests their safety and effectiveness. In Canada you can purchase Health Canada approved (Search each product by number here):

  • homeopathic sea water — DIN-HM 80017767
  • homeopathic insulin — DIN-HM 80016480
  • homeopathic granite — DIN-HM 80012752
  • homeopathic roasted sponge “Spongia Tosta” — DIN-HM 80011377
  • homeopathic chloroform DIN-HM 80010524
  • homeopathic table salt DIN-HM 80005389

There are hundreds more, including more well known products like Oscillococcinum and Traumeel, all deemed safe and effective.

It’s easy to laugh at the irony of homeopathic water, and the while the sale of homeopathy by health care providers is certainly unethical, when used for self-limiting conditions, the risk of harm may be slight. But a framework that gives a veneer of credibility to sugar pills increases the perception that homeopathy has legitimate medical uses. This has been observed worldwide with homeopaths descending on Haiti or treating HIV in Africa, illustrating that proponents lack any insight into the lack of objective effects. Just recently, the government of Madhya Pradesh, a state in India, announced a plan to use homeopathy to prevent malaria outbreaks. When homeopathy is used as a substitute for real medical treatments, the risk of harms are real, not theoretical. So I was concerned to to see the following in the Calgary Herald:

A Calgary business that aims to bring traditional homeopathic remedies to the mainstream public has received Health Canada approval for its first locally developed product. Mozi-Q is a natural mosquito repellent created by Calgary-based Xerion Dispensary. The product, made from a plant-derived substance called staphysagria, is taken orally and is advertised not only as a bug repellent, but as a product that will also lessen the stinging and itching associated with insect bites.

which also noted

All natural health products — including homeopathic remedies — sold in Canada are subject to the Natural Health Products Regulations, which came into force on Jan. 1, 2004. Only after Health Canada has assessed a product and decided it is safe, effective and of high quality, will a product be approved.

Effective. There it is. Yes, homeopathic insect repellent, approved by Health Canada with licence number 80031902, with the following “Recommended Use or Purpose”:

Homeopathic rememdy [sic] used for reducing the severity and frequency of insect bites.

And what’s in this product? Like most homeopathy, the labeling obscures the lack of active ingredients. I converted the homeopathic labeling to English, and looked for published medical evidence to support the use any of the ingredients – diluted or otherwise.

  • “cedron 4C:” This is Simaruba Ferroginea, commonly called Rattlesnake Bean in a 10−8 dilution (i.e., 0.000001%) — This product is related to the pinto bean. It is likely nontoxic, especially at this dilution.
  • “grindelia 6C”: Grindelia Robusta or Gumweed in a 10−12 dilution (i.e., 0.0000000001%) — This ingredient is considered “Possibly Safe” at non-homeopathic doses by the Natural Medicines Comprehensive Database
  • “ledum palustre 3X” : Marsh Tea in a 10−3 dilution (i.e., 0.1%) — This ingredient is considered “Likely Unsafe” at non-homeopathic doses by the Natural Medicines Comprehensive Database, causing kidney and urinary tract damage as well as central nervous system excitation.
  • “staphysagria 4X”: Delphinium staphisagria or Stavesacre in 10−4 dilution (i.e., 0.01%) — This ingredient is considered “Likely Unsafe” at non-homeopathic doses by the Natural Medicines Comprehensive Database, as it is poisonous.
  • “urtica urens 6X” : Stinging nettle in a 10−6 dilution (i.e., 0.0001%) — This ingredient is considered “Possibly Safe” at non-homeopathic doses by the Natural Medicines Comprehensive Database.

Interestingly, some of the ingredients aren’t diluted past the “12C” level, the point at which Avogadro’s constant establishes that there isn’t likely to be a single molecule of the original ingredient. The 3X dilution of Marsh Tea is only a 1:1000 dilution. Should we be concerned about toxicity? The manufacturing process, which involves dilution of a “mother tincture” of the initial product, means that the final dilute solution will only contain trace amounts of ledum. That final dilution is then sprayed on tiny sugar/lactose pills, so the final product isn’t likely to have a detectable trace of the original plant.

But setting aside the ingredients, does Mozi-Q work? There is no published evidence that demonstrates that any component of Mozi-Q, either alone or in combination, have any effect on either reducing the frequency of insect bites” or “reducing the severity of insect bites”. The manufacturer states the following:

Has it been studied?
In the ’60s a homeopath by the name of HR. Trexler studied Staphysagria for its effectiveness at preventing mosquito bites. In a study of 421 subjects over a 4 year period, he found this remedy to be 90% effective.

Tried and True!
We have tested this remedy in our clinic over four mosquito seasons and found the response from the public confirmatory of Trexler’s findings.

And that’s the sum total of the evidence — which appeared to be adequate for Health Canada, who granted the “safe and effective” imprimatur of legitimacy. A published report from Trexler does date back to 1965, and it’s not available. There are no other published reports with the product, according to PubMed. Trexler’s US patent registration from 1956 is online, claiming that staphsagria is an effective insect repellent. No evidence of a formal evaluation is described. A patent, of course, doesn’t establish efficacy. Given the totality of evidence has failed to show that homeopathy has any meaningful clinical effects, I am skeptical that a homeopath identified an effective homeopathic oral insect repellent in 1956, and subjected it to a rigorous evaluation in the 1960′s. In any case, it would be easy to prove if it does work – it could be evaluated like every other insect repellent on the market.

How Real Insect Repellents work

For many of us, insect bites are an occasional annoyance that we can largely avoid. Yet insects can transmit over 100 diseases, including malaria, West Nile virus, yellow fever, Dengue fever, Lyme disease and even plague. Malaria alone kills 1.2 million people, mainly African children, annually. And now that we have West Nile and Lyme disease in Canada, there is a bigger impetus to minimize bites. Given the importance of repelling insects effectively, validated methods have been created to test new products.

While it’s not definitively established what attracts insects to bite, carbon dioxide and lactic acid seem to be important factors. In light of this, it’s not surprising that no oral product has ever been demonstrated to effectively work as an insect repellent. In order for an oral product to effectively repel insects, we’d have to consume enough that it would be absorbed and somehow secreted to the extent that it would repel insects – preferably without killing us, first. What does work, beyond physical barriers, are chemical products that we apply to our skin. The most common ingredient in repellents is N, N- diethyl-3-methylbenzamide, more commonly known as DEET, although there are several other chemicals that have been approved for use in consumer products.

How do you know if an insect repellent works? You offer your forearm up as a meal. Consumer Reports illustrates the testing nicely. The US Environmental Protection Agency specifies testing requirements in detail. Its approval outlines the duration of effectiveness as well as detailed descriptions of the efficacy and safety evaluations. In Canada, similar regulation rests with the Pest Management Regulatory Agency. When I asked the PMRA by email how a homeopathic remedy could be possibly be approved as an insect repellent, they replied with the following:

Please be advised that, according to the Pest Control Products Regulations (PCPR), pest control products that are used for the control of arthropods on or in humans or animals can be exempted from the Pest Control Products Act (PCPA), and made subject to the Food and Drugs Act (FDA), if the control product is to be administered directly and not by topical application. If the action of the product is not due to the simple presence of the active ingredient on the skin (the intent of topical application under the PCPA) but rather that the active ingredient has to be absorbed first before it can exert its effect, this is not considered to be a topical mode of action. This would be the case for mosquito repellent patch products. Even though the patch is to be applied to the surface of the skin, the PMRA does not register any pesticide that’s to be taken orally. Based on this systemic mode of action, as per a previous agreement between PMRA and Health Products and Food Branch (HPFB), the type of product you describe in your email would fall under the jurisdiction of HPFB.

Is there a facepalm emoticon? There is no “systemic mode of action” that has been demonstrated for homeopathy. There is no evidence that any oral products are effective as insect repellents. In the United States, a product like Mozi-Q which lacks published evidence of efficacy would not likely be permitted, (homeopathy or not) as there is a federal regulation on oral insect repellents in place, which notes:

Labeling claims for OTC orally administered insect repellent drug products are either false, misleading, or unsupported by scientific data.

Any OTC drug product that is labeled, represented, or promoted for oral use as an insect repellent is regarded as a new drug within the meaning of section 201(p) of the Federal Food, Drug and Cosmetic Act for which an approved new drug application under section 505 of the act and part 314 of this chapter is required for marketing. In the absence of an approved new drug application, such product is also misbranded under section 502 of the act.

Clinical investigations designed to obtain evidence that any drug product labeled, represented, or promoted OTC for oral use as an insect repellent is safe and effective for the purpose intended must comply with the requirements and procedures governing the use of investigational new drugs set forth in part 312 of this chapter.

Yet these products are being deliberately exempted from testing in Canada, and Health Canada is approving them in the absence of any published evidence to demonstrate they work.


When Health Canada removes scientific barriers to product approvals, we should not be surprised by what emerges. Homeopathic insect repellent that has been deemed “safe and effective” provides yet another example of consequences of regulating homeopathy. Consumers who rely on regulators to test and approve products don’t care how a product is licensed – they want assurance that it works. Because while insect bites can be a nuisance, they can also be deadly. Who will be responsible if a consumer contracts a insect-borne disease if they use homeopathy instead of effective insect repellents: The manufacturer, or the regulator? In the absence of adequate regulation, the science in this case is very clear: if you want to reduce your risk of insect bites and their consequences, use real insect repellents — not homeopathy.

15 Responses to “Homeopathic Insect Repellent: Is there anything the Natural Health Products Directorate won’t approve?”

  1. richard says:

    I wonder if there would be legal precedent for suing Health Canada on the basis that they are approving products as effective when the data do not support such claims?

  2. Jason says:

    A general comment about the blog, as I am not sure exactly where best to post. Has anyone else noticed that the majority of the articles focus on health and medical claims, mainly medicinal remedies? ( perhaps a result of the area of interest / expertise of the main contributors … which are of course well received ) Goodness knows there is a wide variety of topics and issues worthy of skeptical inquiry other than the very important area of health and wellness. I do believe more variety of articles would be most welcomed ( comments? ) and though I realize one possible solution is to contribute myself, I hope this comment alone may be helpful.

  3. Linda Miller says:

    If you are so sure that homeopathic remedies are only placebo, then apply the scientific method and try it. You will find that Mozi-Q works as indicated whether you or a child or pet believe it or not.

    • Scott Gavura says:

      That’s not how science works, Linda. The burden of proof is on those making the claim. If sugar pills are an effective insect repellent, I invite the manufacturer to back those claims up with some credible evidence.

    • Dianne Sousa says:

      Ms. Miller,

      I see that you are a homeopath at Xerion homeopathie – the manufacturer of Mozi-Q. The website indicates that the clinic was founded by your daughter, so I think it’s fair to say you have an interest in having the product succeed.

      Since you are the manufacturer, perhaps you can provide us with information regarding the testing you conducted on your product. I’d be very interested in reading the proving.

  4. Heather says:

    i just bought mozi-q today directly from Xerion homeopathie. ***it did NOT work*** the instructions (and the lady at the store who sold it to me) told me to take it 30 minutes before i went outside. she said to chew the pill a tiny little bit and then place it under my tongue so it can be absorbed sublingually, so i let it fully dissolve. it says it will work for 3-5 hours. i took it at 830pm i went outside at 10pm braved the outdoors in my backyard of urban suburban calgary, and i got 11 big mosquito welts in 15 min … and then ran inside frantically searching for my afterbite

    so $26.24 for 60 tabs… i should have wasted that money at stampede instead, so now i’m going back to my citronella spray with essential oils of eucalyptus & tea tree as that at least worked for me for the most part

  5. A little too skeptical placebo in the days of scientific advancement. I really advice people not to waste money on such things. Go by the scientific ways.

  6. When there seems to be so much advancement in science this comes across as a faker. There has always been controversial arguments over Homeopathy. I kind of feel it is not much efficacious.

  7. I wonder if there would be legal precedent for suing Health Canada on the basis that they are approving products as effective when the data do not support such claims?

  8. I can’t say exactly what herbs they use but I have seen Asian people to mix some of the leaves’ juices and then they fill it in the regular repellents, electrically operated. Though frightened I was curious and found that it worked to repel and also gave a decent aroma. Now, has homoeopathy found something similar? May be or we are tricked. In such situations it is necessary to keep eyes and ears open and be a hardcore sceptic. That can work.

  9. Agence Tourisme Dentaire says:

    God has given us so many things on this earth which has its own utility.As we do not understand the secret of nature, we try allopathy or homeopathy medicines. Most of them are safe, but some are harmful to our body. Before using any medication we should try to check its effects and then use it. But it is always better to first try natural remedies. One of the best way to keep mosquitoes at bay is to burn dried neem leaves in your backyard and allow the smoke to enter your home. This will surely kill mosquitoes. The same is also true with garlic skin.


  1. [...] Canada has this thing where it solemnly approves homeopathic stuff as safe, effective and of high quality. What kind of stuff? you ask with your inquiring minds. Oh, [...]

  2. [...] Skeptic North examines some of the other ridiculous items that Health Canada has recently approved. It’s an excellent source for more information regarding the limitations and flaws in our national drug regulating body, Health Canada. Also if you want to curse out these homeopathy scam artists and shake your fist at a computer screen. Share this:TwitterFacebookLike this:LikeBe the first to like this. This entry was posted in Mythic Mondays and tagged Canada, Homeopathy, Myths, Quack Cures, Science, Skepticism, Woo.Bookmark the permalink. Leave a comment [...]

  • Scott Gavura

    Scott is passionate about improving the way drugs are used. A pharmacist by background, Scott has a professional interest in improving the cost-effective use of drugs at the population level, while helping consumers make more informed decisions about their health. He blogs about pharmacy practice and questionable science at Science-Based Pharmacy and Science-Based Medicine. All views expressed by Scott are his personal views alone, and do not represent the opinions of any current or former employers, or any organizations or associations that he may be affiliated with. All information is provided for discussion purposes only, and should not be used as a replacement for consultation with a licensed and accredited health professional.