Posted By Richard Maundrell, Associate Professor, Lakehead University
In 1994 changes to the Food and Drugs Act made Health Canada responsible for the regulation of natural health products and homeopathic medicines (NHP’s). Since then, thousands of NHP’s have been approved by Health Canada as safe and effective. I argue that Health Canada’s criteria for efficacy in relation to NHP’s in particular are inadequate and that its certification of NHP’s is a betrayal of the trust that health care consumers have placed in a bureaucracy that is responsible for the regulation of prescription medicines. In Part One of this two-part blog series, I explain what homeopathic medicine is and why it is pharmacologically implausible. In Part Two, I look at Health Canada’s certification process and the problems with its criteria for efficacy in application to NHP’s.
Part I
A decade has passed since Parliament revised the Food and Drugs Act to include natural health products (NHP’s) within the regulatory ambit of Health Canada. The legislation applies to products that had been available in the marketplace for years, but which had escaped regulation because they were neither foodstuffs nor prescription medicines. These products included vitamins, minerals and herbal remedies as well as homeopathic and traditional medicines. Initially, the changes seemed to be a promising development for consumer protection, because they required manufacturers of NHP’s to prove the medicinal claims they used to market their products. Properly executed, the regulation might have helped to rid the drug store shelves of products sold on the basis of misleading, exaggerated or outright fraudulent claims of medicinal properties. Unfortunately for Canadian healthcare consumers, that is not how things worked out. Just how misguided Health Canada’s policies have been in this area is evident in its regulatory policies concerning homeopathic medicines.
What is Homeopathy?
While homeopathy is often confused with herbal medicine, it is actually a distinct mode of alternative medical treatment conceived and developed in the late 18th century by Samuel Hahnemann (1755-1843). Unlike modalities of alternative medicine that have emerged from traditional folk practice, homeopathy is based on theoretical principles. Its pharmacology is based on Hahnemann’s “Law of Similars”: the principle that a substance which produces the symptoms of a disease in a healthy person will be effective in treating a disease involving those same symptoms in someone who is ill. Thus a common homeopathic treatment for nausea is extracted from the root of the Carapichea ipecacuanha plant, which is known to cause nausea and vomiting in otherwise healthy subjects. Hahnemann developed this “fighting fire with fire” approach using “provings”: an experimental method that tests the effects of potential medications on healthy subjects rather than sick ones. Medicines developed in this way would invite obvious concerns about toxicity if not for the other founding principle of homeopathy, the “law of infinitesimals,” which asserts that the smaller a dose of medication the more powerful its effect.
Consistent with the law of infinitesimals, homeopathic medications are prepared through an elaborate process of dilution in which the “mother tincture” is mixed at a ratio of one part active ingredient to 100 parts solvent (usually water). From its initial dilution the preparation can be diluted again any number of times, each by a factor of 100. Thus a 1:100 or “1C” solution becomes a 2C solution by being diluted again by a factor of 100, yielding a ratio of medicinal ingredient to diluent of 1/100 x 1/100 or 1:10,000. Homeopathic medications are often 20C, which means that they are the product of a series of twenty dilutions, each by a factor of 100. Aside from dilution, the preparation of homeopathic medications involves “succussion” or rhythmic shaking so as to impart the “pharmacological message” of the original substance to the molecules of the diluent.[1]
Is Homeopathy Medicinally Effective?
According to conventional science, homeopathic preparations will quickly become biologically and medicinally ineffective as the dilution process proceeds. At 30C, for example, one part active ingredient will remain in 1060 parts solvent. The chances that a single molecule of active ingredient will remain in a standard dose of 30C homeopathic medicine is one in a billion, billion, billion, billion.[2] In the face of the basic implausibility of Hahnemann’s principles, homeopaths have continued to search for a scientific grounding for their beliefs. In the 1980’s, biochemist Jacques Benveniste claimed that he had observed reactions in human basophil samples to homeopathic-scale dilutions of the anti-IgE antibody.[3] To explain his observation, he hypothesized the notion of “the memory of water”: the idea that water is somehow capable of retaining the chemical properties of substances that are immersed in it. However, Benveniste was unable to replicate these results when asked to do so under properly blinded conditions by an investigative team from the journal Nature.[4] This lack of replication has traditionally been the barrier preventing pre-clinical research in homeopathic ultra-dilution from acceptance as genuine science.[5] The homeopathic community has an onerous burden of proof to establish that homeopathic medicines should be considered anything but placebo treatments.
Hahnemann practised medicine in a time prior to the advent of scientific medicine and the germ theory of disease when blood-letting was still a common mode of treatment for many illnesses. If his treatments were ineffective, they were probably not noticeably less so than what his peers were offering.[6] However, in light of the progress medical science has made since Hahnemann’s time, as well as the scientific implausibility of homeopathy’s theoretical tenets, we might reasonably expect regulatory agencies like Health Canada to demand substantial evidence of efficacy in homeopathic medications. After all, extraordinary claims demand extraordinary evidence. Compelling evidence of efficacy in homeopathic medications, however, remains elusive.[7] In a report to the British House of Commons in 2010, an investigative committee examining published research on homeopathy stated that “systematic reviews and meta-analyses conclusively demonstrate that homeopathic products perform no better than placebos.” That finding was echoed by a similar study carried out for the Australian government in 2013. While noting the paucity of high-quality clinical studies on homeopathic treatments, its authors concluded: “the available evidence is not compelling and fails to demonstrate that homeopathy is an effective treatment for any of the reported clinical conditions in humans.”
Meta-analyses cited by the British and Australian studies filter out low quality studies and reserve the greatest significance for the results of randomized clinical trials (RCT’s). The effectiveness of a medication is most accurately measured across subject populations that, for comparison purposes, have been randomly assigned to treatment and control groups. Random distribution reduces the probability that extraneous differences between subjects might be mistaken for therapeutic effect. The use of controls enables the application of statistical methods to arrive at a picture of therapeutic effect that is as precise as possible in research on human subjects. RCT methodology has been refined continuously since its introduction, most importantly with the introduction of placebo controls and double-blinding that enables researchers to tune subject and researcher expectations out of their data.[8] The RCT became the most trusted method available to medical research because it provided the most effective means of eliminating confirmation bias from the interpretation of clinical outcomes: the very common and natural human tendency to assign undue significance to evidence that supports one’s beliefs and to discount evidence that counts against them. It is principally on the grounds of RCT data that regulatory agencies like Health Canada approve prescription drugs.
Health Canada holds NHP’s to a much lower set of standards than those which it applies to prescription drugs. Those who drafted Health Canada’s policies on the regulation of homeopathic medicines must know that they are too dilute to be pharmacologically effective, and yet Health Canada’s guidelines for the approval of homeopathic medicines stipulate 12C as the minimum allowable potency (in the homeopathic sense of the term ‘potency’). Given that homeopathic medicines commonly have a potency of 20C, the vast majority of homeopathic medicines meet this criterion.
There is no known causal mechanism by which a 12C solution, diluted as it is to one part in 10-24, can have biological effects, medicinal or otherwise. At 12C dilution, it has become a significant possibility that not even a single molecule of the original substance remains. Unless we have reason to believe that water really does have a memory, a solution that contains no medicinal ingredient can have no medicinal effect. The same facts that make homeopathic products safe for non-prescription use explain why such products can have no medicinal benefits beyond placebo. This leads one to wonder what Health Canada’s certification of an NHP as “effective” actually means. This will be the subject of Part II.
[1] Simon Singh & Edzard Ernst, Trick or Treatment: The Undeniable Facts about Alternative Medicine, (New York: W W Norton,2008) at 98.
[2] Singh & Ernst, supra note 1 at 99.
[3] Elizabeth Davenas et al, “Human Basophil Degranulation Triggered by Very Dilute Antiserum Against IgE” (1988) 333 Nature 816.
[4] John Maddox, James Randi & Walter W Stewart, “High Dilution Experiments a Delusion” (1988) 334 Nature 287.
[5] AJ Vickers, “Independent Replication of Pre-clinical Research in Homoeopathy: A Systematic Review” (1999) 6:6 Research in Complementary Medicine 311.
[6] Steven Bratman, The Alternative Medicine Sourcebook: A Realistic Evaluation of Alternative Healing Methods, 2d ed (Los Angeles: Lowell House, 1999) at 104.
[7] Edzard Ernst, “Homeopathy: What Does the Best Evidence Tell Us?” (2010) 192:8 Medical Journal of Australia 458. (This article is a review of all systematic reviews conducted on homeopathy in the Cochrane Database of Systematic Reviews, which is generally considered the most reliable source of evidence.)
[8] Marcia L Meldrum, “A Brief History of the Randomized Controlled Trial: From Oranges and Lemons to the Gold Standard” (2000) 14:4 Hematology/Oncology Clinics of North America 745.
McGill Journal of Law and Health 