Introduction
Homeopathy is a system of health care that was originated in 1796 by a single individual, Samuel Hahnemann, a German doctor who was critical of the medicine of his time. It is a discipline practiced by homeopaths, but homeopathic remedies are also sold over the counter in pharmacies for customers to self-treat. Homeopathy is arguably the most implausible branch of so-called alternative medicine (although energy medicine would be a close contender; and in a way, homeopathy amounts to a form of energy medicine). It is a pseudoscientific system based on the belief that “like cures like.” Its remedies dilute the original ingredient into nonexistence. Its tenets are in direct opposition to established scientific knowledge. In order to accept homeopathy, we would need an overwhelming body of evidence sufficient to outweigh basic, well-established principles of physics, chemistry, and biology. There is no such evidence. Despite two centuries of research, homeopaths have failed to establish homeopathy’s effectiveness; and multiple respected organizations have reviewed the evidence and have issued statements saying that homeopathy doesn’t work. Nevertheless, many people continue to believe in it because of their personal experiences. Many of them have no understanding of what homeopathy is, thinking that it’s just some kind of “natural” or herbal medicine.
The history of homeopathy
Homeopathy was developed in the 1790s by a German doctor, Samuel Hahnemann (1755-1843). To understand what happened, it’s important to consider his invention in the context of the state of medicine at the time. Medicine was still in its infancy. It was based on superstition and tradition rather than on science. There was no germ theory of disease, no antibiotics, doctors didn’t wash their hands. Surgery was done without anesthesia and with no sterile precautions. There was no concept of testing treatments with randomized placebo-controlled double-blind trials or indeed, of testing them at all. Doctors weakened their patients with emetics, purges, and bloodletting. They poisoned them with mercury and other dangerous drugs. The number of safe, effective drugs could be counted on the fingers of one hand. As late as 1860, Oliver Wendell Holmes would say, “I firmly believe that if the whole material medica, as now used, could be sunk to the bottom of the sea, it would be all the better for mankind—and all the worse for the fishes.” Quite frankly, doctors did more harm than good throughout the 19th century. It wasn’t until around 1900 that patients stood more than a 50/50 chance of benefiting from an encounter with a doctor.
Hahnemann soon became disillusioned with medicine. He realized that the treatments he had been taught in medical school were not helping the patients who consulted him, and the income from his medical practice was not enough to support his growing family; he supplemented his income by writing and translating. In 1791, when he was translating Cullen’s Materia Medica, he questioned what it said about Cinchona, a medicine derived from the bark of a Peruvian tree. Cinchona and its derivative quinine are effective treatments for malaria, but Hahnemann rejected Cullen’s explanation of its mechanism of action. He experimented by taking Cinchona himself, and he developed what he thought were the symptoms of malaria. Later experts have concluded that he probably had an idiosyncratic allergic reaction or intolerance to the drug, and subsequent studies showed that it did not reproduce the same symptoms in other people.[1] Hahnemann thought he had shown that a drug that cures malaria would cause the symptoms of malaria in a healthy person. By extrapolation, he formulated the principle of similibus curantur, or “like cures like.” He said, “Any substance which can produce a totality of symptoms in a healthy human being can cure that totality of symptoms in a sick human being.” Giving the undiluted substance caused adverse reactions, so he kept diluting his remedies until patients no longer experienced side effects, and he used “succussion,” vigorously shaking the remedy and striking the vial on a leather-bound Bible or on a board he had designed for the purpose, covered in leather and stuffed with horsehair. He believed this “potentized” the remedy by somehow releasing the energies of its medicinal powers.
These ideas were not entirely original. Hippocrates and others had used small doses of remedies that caused symptoms of the disease in large doses. Indigenous shamans and the European herbalists of Hahnemann’s time had a tradition of vigorously shaking their medicines to “wake them up.” But Hahnemann was the first to develop these ideas into a formal system of medical treatment. He called it homeopathy, from the Greek words homoeos for similar and pathos for suffering. He coined the word allopathy (opposite + suffering) to denigrate the orthodox medicine of his time, which he characterized as only treating the symptoms, not the disease itself, and using remedies that produced effects that were opposites rather than similars. Treating with “opposites” was never the guiding principle of medicine even in Hahnemann’s time, and using the word allopathy to refer to today’s mainstream medicine is not only incorrect but insulting; doctors who are aware of the history object to being called allopaths.
Hahnemann published numerous articles and books, most notably his Organon of Rational Art of Healing in 1810. He proceeded to practice homeopathy despite strong resistance from orthodox doctors and apothecaries. Gradually, some other doctors began to follow his lead. By the late 1800s, homeopathy had spread to over 30 countries. In 1844, homeopaths founded the first medical organization in the US.[2] By 1900, a quarter of all MDs in the US were homeopaths, and a homeopathic hospital in Philadelphia was one of the best equipped, largest hospitals in the world.[3] At homeopathy’s peak there were 22 homeopathic medical schools and more than 100 homeopathic hospitals in the US.
In the early 1900s, as mainstream medicine became more scientific and more effective, the popularity of homeopathy began to decline. The 1910 Flexner Report[4] recommended measures to raise the standards of medical education, resulting in the closure of many homeopathic and other sub-standard medical schools. The last homeopathic medical school in the US closed in 1920, and by the 1970 there were only 75 pure homeopaths practicing in the US.
Royal Copeland, a homeopath who was also a US Senator, was a sponsor of the Federal Food, Drug, and Cosmetic Act of 1938, and his influence contributed to getting homeopathic remedies “grandfathered in” and exempted from the regulations applied to other drugs. They are legal as long as they are listed in HPUS, the Homeopathic Pharmacopeia of the United States. There is no requirement to show that they are safe or effective.
Since the advent of so-called “alternative medicine” in the late 20th century, there has been a resurgence of interest in homeopathy. Training in homeopathy is an integral part of the curriculum in schools of naturopathy, and many MDs and other practitioners (chiropractors, acupuncturists) are prescribing homeopathic remedies to their patients. Uninformed consumers think of homeopathy as a natural herbal approach to healing: a kinder, gentler alternative to harsh drugs. Homeopathic remedies are sold on the shelves of most pharmacies for customers to pick and choose and treat themselves, a practice Hahnemann would have vehemently rejected. There are even homeopathic first aid kits for sale. One kit[5] has 18 vials of tiny pills and instructions on using them to treat conditions that need much more than first aid, including anaphylaxis, burns, animal bites, electrocution, puncture wounds, carbon monoxide poisoning, shock, and much more. In a recent development, the FTC ruled in 2016 that homeopathic remedies can’t make claims of effectiveness without “competent and reliable scientific evidence;” and if no such evidence exists, they must divulge that information clearly on their labels and in their advertising.[6] It remains to be seen whether such labeling will have any impact on sales.
Homeopathy remains popular in many countries, especially in Europe and India. In the UK, the royal family is devoted to homeopathy and even maintains a court homeopath.[7] As recently as 2009 there were still four homeopathic hospitals in the UK; all have either closed or changed their names to omit the word homeopathy.[8] The UK’s National Health Service still pays for some homeopathic remedies, but that’s declining thanks in part to activists like Michael Marshall and the Good Thinking Society.[9] Skeptics including James Randi have staged individual and mass worldwide demonstrations where they have taken overdoses of homeopathic remedies to make the simple statement “Homeopathy – There’s Nothing in It.”[10]
The principles of homeopathy
The two core principles of homeopathy are the Law of Similars (like cures like) and the Law of Infinitesimals (the smaller the dose, the larger the effect). But the principles are described differently by different homeopathy resources. One of the more comprehensive descriptions[11] lists these seven major principles:
- Law of Similia.
- Law of Simplex
- Law of Minimum
- Doctrine of Drug Proving
- Theory of Chronic Disease
- Theory of Vital Force
- Doctrine of Drug-Dynamisation
- Law of similia. Similia similibus curantur, “Let likes cure likes.” A substance that causes symptoms of a disease in a healthy person will elicit a healing response in a patient with the disease. To choose the appropriate remedy, the homeopathic practitioner matches the symptoms elicited by the substance to the symptoms of the patient, with particular attention to symptoms that may not be characteristic of the disease but are unique to that individual.
- Law of simplex. The single remedy. In classical homeopathy, only one remedy is given at a time, because homeopathic knowledge is based on testing remedies singly, and because only one remedy can be most similar to the condition of the patient at a given time.
- Law of minimum. Remedies are given in minute doses to avoid unwanted aggravation.
- Doctrine of drug proving. Homeopathic remedies must be tested by “provings” on healthy people to learn their curative properties.
- Theory of chronic disease. Despite his best efforts at homeopathic treatment, Hahnemann found that some cases stubbornly recurred. By investigating a large number of chronic cases, he determined that chronic diseases are caused by chronic “miasms.” The miasm Psora is the “mother of all diseases” and is the cause of 7/8 of disease; and the remainder are due to the other two miasms, Syphilis and Sycosis.
- Theory of vital force. The idea that an immaterial vital force animates the human organism and maintains normal functions. If it is dynamically deranged, the signs and symptoms of disease are manifested. If the vital force is too debilitated, nothing can effect a cure.
- Doctrine of drug dynamization. Dynamization is a process by which the latent medicinal properties of natural substances are awakened. They are potentized by a process of vigorous shaking known as succussion. This process renders poisons harmless and transforms substances into healing remedies with no side effects.
The principles of homeopathy are incompatible with science
For these “laws,” principles, and doctrines to be proven true, much of our established knowledge about physics, chemistry, and biology would have to be proven wrong.
To show how monumentally silly Hahnemann’s principles are, it is helpful to consider a simple example. According to homeopathy, if coffee keeps you awake, dilute coffee will put you to sleep. The more dilute the coffee, the better it will work as a sleep remedy. If you keep diluting it until there is no longer a single molecule of coffee left, it will be even more effective. If you drip the resulting liquid (devoid of coffee) onto a sugar pill and let it evaporate, the sugar pill will somehow remember the coffee and will be an effective sleep remedy.
Established scientific knowledge is incompatible with each of the homeopathic principles as listed above.
- Law of similar (treating with the same substance that causes symptoms of the disease). This akin to magical thinking, the same kind of associative thinking that led herbalists in the Middle Ages to believe that if a plant resembled a body part, it would be effective in treating diseases of that body part. Hahnemann’s original observation, that a cure for malaria (cinchona) produced the symptoms of malaria in a healthy person, was an error on his part, and was discredited by later trials on other people. There is no credible evidence, and no rationale, to support the principle that any substance that causes the symptoms of a disease will cure that disease.
- Law of simplex. (Only one remedy at a time.) Modern medicine provides many examples of conditions that don’t respond to a single drug, but to combinations of drugs. For instance, Helicobacter pylori infections, which cause stomach and duodenal ulcers, are effectively treated only with a combination of three drugs. And there is no reason to think there is a unique remedy for each individual patient. Quite the contrary. Prescription drugs are approved for marketing on the basis of studies on groups of patients showing that the drugs work similarly for most patients. Penicillin cures syphilis in every patient.
- Law of minimum, also called the Law of Infinitesimals. The original idea was to use the smallest possible effective dose to minimize the chance of side effects. The biggest problem with this “law” is that homeopaths don’t just use minimum doses, they regularly use nonexistent doses. When Hahnemann developed his dilutions, Avogadro’s number had not yet been discovered, so Hahnemann had no way of knowing how much of the original substance remained at each stage of dilution.
A 6X dilution means that one part of the original substance is diluted in nine parts of water or alcohol (for a one in ten dilution, where X = 10), then one part of the resulting liquid is again diluted in nine parts of liquid, and so on for a total of six times, resulting in one part per million. A 6C dilution means one part of remedy is diluted in 99 parts of liquid (for a one in a hundred dilution, where C = 100) and the process repeated six times, resulting in one part per trillion. Substances not soluble in water are ground up (triturated) and diluted with lactose (milk sugar). Avogadro’s number can be used to calculate that by the 26X or 13C dilutions, there are no molecules of the original substance left. The typical homeopathic remedy is 30C. At that level, it would take a container 30 million times the size of the Earth to hold enough water to make sure you were getting at least one molecule of the original substance. And many homeopathic remedies are even more dilute; above the 1000C level, they are designated as M, where M = 1000C.
Tiny dust particles fall from the air into any open container. No container is ever 100% free of contaminants. There must be traces of impurities in the original substance. By the time the final dilution is made, there are bound to be more molecules of contaminants than of the original substance.
The most popular homeopathic flu remedy, Oscillococcinum, is sold as a preparation of 200C, for a concentration of one part in 10 to the 400th power. The number of atoms in the observable universe is many orders of magnitude smaller, 10 to the 80th power. And to make it even more ridiculous, there’s no such thing as Oscillococcinum! That’s the name given to a nonexistent species by someone who imagined he saw oscillating bacteria under a microscope in the blood of flu victims. No one else ever saw them. He imagined he saw the same bacteria in a duck, so the Oscillococcinum remedy is prepared today by grinding up the heart and liver of a Muscovy duck and then diluting it by 1:100 two hundred times. One might say that the duck is diluted out until all that is left is the quack.
When homeopaths realized their remedies were nothing but water (or alcohol, or sugar), they came up with hypothetical metaphysical explanations, saying that the remedy somehow magically retained a memory or imprint of the original substance.
Part of the Law of Infinitesimals is the claim that the more dilute the remedy, the more powerful its effect. That isn’t how the world works. For everything else, the more dilute, the less effective. If you reduce the amount of sugar in your coffee, it doesn’t become sweeter. If you dilute red, you get pink, not a more vivid red. The guiding principle of toxicology is “the dose makes the poison;” if you ingest a small enough dose, a poison won’t harm you.
While homeopathic remedies usually contain no active ingredient, some of the lower potency remedies do, and poor quality control in the manufacturing process can result in amounts larger than intended. The FDA recently issued a warning[12] about homeopathic infant teething remedies that contained dilute belladonna. They had received numerous reports of seizures and other adverse reactions that were attributed to belladonna poisoning.
- Doctrine of drug proving. Real medicines are tested with randomized placebo-controlled double-blind trials; homeopathic remedies are tested with “provings,” which are typically uncontrolled and unblinded. A remedy is taken by a small number of healthy volunteers and they keep a detailed diary of everything they experience. There is no attempt to rule out symptoms that might be unrelated to the remedy, and everything reported is then included in the Repertory for that remedy.
A 1999 proving from the New York School of Homeopathy is reported with extensive details online.[13] I encourage you to read the report: it’s truly mind-boggling. The “proving” was of the common housefly. They obtained a fly pupa, ground it up, and prepared 12 vials of 30C potency (i.e., no remaining molecules of fly). 10 healthy individuals took the remedy; they were not told what the remedy was, but there was no other attempt at blinding, and no control group. The experimenters, who called themselves “Master Provers,” slept with the remedy under their pillow and “experienced strong symptoms.” The ten subjects reported hundreds of symptoms, which they categorized into 37 areas such as eye, ear, fears, dreams, food, face, smell, stomach, etc. To give just a few examples:
- Under the category Hearing, two symptoms are listed: “noises, like honey” and “sounds are stretched.”
- Dreams: a whopping 82 are listed: dreams of toilets, of a red dress, nuns, swimming, picking sores until they bled, elevators, black dogs, boats, bombs, flying, red hair, homosexuals, money, monsters, and on and on.
- Food and Drink: desires for bacon, coffee, chocolate, heaviness alternating with lightness, lassitude, weakness, sensation of paralysis, and 11 more.
- Mouth: spongy gums, fetid odor of breath, taste of lemons in mouth, lower gum line feels thin and stings, and 8 more
Other reported symptoms included toothache while eating chocolate, appetite wanting, awkwardness, cold feet, desire to masturbate, flaccid penis, greasy skin, snoring during nap, and hundreds more. Instead of looking for commonalities, all the symptoms reported by all the subjects are simply pooled together.
It is obvious that some of these symptoms are due to an overactive imagination or delusions, others are things that any normal person might report in the course of daily life (surely people might experience a desire to masturbate at other times when they are not taking a remedy in a proving), and none can be contributed to the house fly, which has been diluted out of existence.
All the symptoms that have been collected from provings like these are listed in two books: a Repertory organized by symptoms and a Materia Medica organized by remedy. The homeopath peruses those books in an attempt to find the remedy whose symptoms best match the symptoms of the patient. Hahnemann listed 67 remedies; today there are over 2000. Anything can be a remedy. Some examples: Berlin Wall, eclipsed moonlight, south pole of a magnet, dog’s earwax, tears from a weeping young girl, fossilized dinosaur bone, rattlesnake venom, arsenic, poison ivy.
- Theory of chronic disease. Hahnemann soon discovered that homeopathy didn’t always work. He developed his theory of miasms[14] to explain the failures of homeopathy in chronic diseases. He claimed that Psora was the fundamental miasm, creating susceptibility to all other miasms and diseases, responsible for 85% of all chronic disease. Contagious by the slightest touch, it is present in every living being. It arose from a skin eruption now known to be caused by the itch mite scabies. A second miasm, Syphilis, is caused by suppressed syphilis and is inherited. The third miasm is Sycosis, or suppressed gonorrhea, which is transmissible to others and is also hereditary.
If this doesn’t make sense to you, don’t worry; Hahnemann just made it all up. These hypothesized “miasms” bear no resemblance to reality; there is absolutely no evidence to support Hahnemann’s assertions. The diseases scabies, syphilis, and gonorrhea are well understood today and are all eminently curable with modern medicines; they do not cause chronic disease, and cannot be inherited.
- Theory of vital force. This is based on outdated ideas. Vitalism is the theory that the origin and phenomena of life are dependent on a force or principle distinct from purely chemical or physical forces. Hahnemann said diseases “…are solely spirit-like (dynamic) derangements of the spirit-like power (the vital principle) that animates the human body.”Modern science has shown that the phenomena once thought to have immaterial causes can be explained in purely material terms as emergent processes. The myth of vitalism has long been rejected by philosophy and medicine alike, but it persists in the “energy medicine” mythology of alternative medicine. Critics of alternative medicine have pointed out that vitalism is incompatible with science.[15]
- Doctrine of drug dynamization. Vigorous shaking (succussion) dynamizes or potentizes remedies to release their healing powers. This quotation from a homeopathy website says it all:
“Potentization, like much of cutting-edge science today, challenges the modern conception of matter. Generally, a remedy above the 12C potency contains no molecules of the substance from which it was made, and yet it has properties which stimulate healing and which are unique to that remedy alone. In other words, even without the molecules that identify it in its material form, the remedy still has qualities that belong to it and not to any other remedy. Moreover, the more highly potentized the remedy, the more clearly these other qualities come through, both in provings and in healing. We can infer that there is something other than molecules that makes substances unique, something that becomes stronger in the process of potentization. This has been described as the energetic aspect of the substance, and sometimes homeopaths use the analogy of electricity or resonance to explain its action, saying that the remedy works by “conveying a charge” to the patient or by matching the patient’s “resonant frequency.”
Partly because of this analogy, homeopathy has come to be known as “energy medicine.” http://www.homeopathycenter.org/homeopathy-today/thought-behind-action-potency-what-it-and-what-it-means
This is not science; it’s special pleading in an attempt to support a belief that is not supported by any scientific evidence. The putative “energy” in “energy medicine” is not detectable by scientists who can measure real energies of all kinds down to the subatomic level. There is no need to assume “something other than molecules” to explain how homeopathy works. There is a much more plausible explanation: it doesn’t work, and people are fooled into thinking it does by their experiences and the foibles of human psychology.
“Homeopathy can’t possibly work as claimed” is the sort of basic science that can reasonably be called established knowledge. The evidence against homeopathy is as strong as the evidence that the planets orbit the sun, mass and energy are conserved, the earth is several billion years old, and species evolved by a process of variation and natural selection.
The homeopathic consultation
When a patient consults a homeopath, the homeopath will typically spend as much as an hour with the patient, asking detailed questions about the chief complaint, questions about general health and family history, food likes and dislikes, sleeping position, dreams, and off-the-wall questions like “What are you teased the most about?” They need to know all these seemingly irrelevant details because that’s the kind of symptoms that are listed in the Repertory. In order to choose the appropriate remedy from the Materia Medica, the homeopath needs to know everything about the patient, from absence of nurturing in childhood to feelings of anger or loneliness. If the patient is anxious, the homeopath has to choose from 66 remedies in the Materia Medica depending on things like whether the patient’s facial expression is “anxious when child is lifted from cradle, anxious during downward movement, astonished, besotted, bewildered, changed, childish, cold, distant,” and so on ad infinitum.
The homeopath picks the remedy whose entries in the book he thinks most resemble the patient’s symptoms. If the patient doesn’t improve, he assumes that the first remedy was correct but is no longer correct because the patient’s condition has changed, so he picks another. There’s always another remedy to try, so the homeopath can keep the patient entertained (and paying for more office visits) until the condition improves on its own. If the patient gets worse, it’s presumed to be an “aggravation,” which proves the remedy is working. Worsening symptoms can also be blamed on the patient: he may have inadvertently done something that acted as an Antidote, such as drinking coffee, not getting enough sleep, using a cellphone, or eating spicy foods. There is always an explanation and an “out,” so the homeopath can never be wrong.
The different kinds of homeopathy
Homeopathy has evolved into various types of practice that Hahnemann would surely not have approved of. Edzard Ernst lists these varieties:[16]
- Auto-isopathy (treatment with remedies made from patients’ own body substances)
- Classical homeopathy (doctrine based on strict Hahnemannian principles)
- Clinical homeopathy (non-individualised treatment based mainly on guiding symptoms; e.g. arnica for bruises)
- Complex homeopathy (treatment with combination remedies)
- Homotoxicology (treatment based on Reckeweg’s concepts of detoxification)
- Isopathy (use of remedies made from the causative agent, e.g. a specific allergen for an allergy)
- Pluralistic homeopathy (use of more than one remedy at once)
There’s more: DIY homeopathy, where consumers with no training in homeopathy buy homeopathic remedies over the counter and self-administer. This is the largest group of all. According to Hahnemann’s doctrines, this couldn’t possibly result in clinical benefit.
And there’s also Bach flower remedies, invented by a homeopath, based on the idea that the dew on flower petals absorbs healing qualities from the plant. The remedies are highly diluted solutions prepared by placing flowers in water and exposing them to sunlight.
And electrohomeopathy,[17] developed by Cesare Mattei in the late 19th century as a nonsurgical alternative to cancer treatment. It involves “red, blue and green” electricity.
And there are more, listed in an article by a Dutch physician in a 1943 PhD dissertation. https://www.skepsis.nl/blog/2016/04/critical-considerations-on-homeopathy/ In constitution theory, symptoms are disregarded and remedies are based on the patient’s constitution, which might be hydrogenoid, oxygenoid, or carbo-nitrogenoid. In cell-salt homeopathy, highly dilute solutions of a dozen important salts were prescribed to correct the imbalances of salts in cells that were the cause of disease. Drainage therapy claims that homeopathic remedies magically drain away the toxins that are the underlying cause of all disease.
Magical thinking. In addition to all of these, there are bizarre anecdotes showing clearly that homeopaths believe in magic.
When a car broke down, one homeopath administered “Electricitas 200C” to the car by writing the prescription on a sheet of paper and placing it near the engine. This was credited with enabling the car to complete a cross-country trip.[18]
Dowsing is sometimes used to select a homeopathic remedy; a pendulum held over the vial swings in a certain way to indicate it is the appropriate remedy.
Homeopaths have treated patients by telephone or telepathy.
In grafting, one potentized sugar pill is added to a bottle of inert pills and it converts them all to remedies.
Provings are done where the subject doesn’t actually take the substance, but meditates about it, dreams with it under the pillow, participates in its preparation, or writes it on a piece of paper and keeps the paper close to the body.
Homeoprophylaxis. In a dangerous development, homeopathic “vaccines” are offered to protect patients from contagious diseases. They are prepared with “Nosodes,” material taken from the saliva, blood, pus, urine, or diseased tissue from victims of the disease. These vaccines are available for everything from anthrax to malaria to smallpox. Health Canada has officially licensed homeopathic remedies to prevent flu, polio, measles, and pertussis.[19]
In a UK study, Alice Tuff, a 23-year-old member of Sense about Science, visited 10 homeopathic clinics and pharmacies saying she was planning a 10-week tour through Central and Southern Africa and the anti-malaria medicines she had been prescribed made her feel queasy. All ten homeopaths recommended she stop the effective malaria prophylaxis[20] and that she use homeopathic prevention instead, in the form of remedies made from a variety of sources including African swamp water, rotting plants, mosquito eggs and larvae, tree bark, and salt tablets. One practitioner told her the homeopathic medicines “make it so your energy – your living energy – doesn’t have a kind of malaria-shaped hole in it. The malarial mosquitoes won’t come along and fill that in. The remedies sort it out.”
Malaria is almost completely preventable but potentially fatal. In 2015 1400 cases were reported in the UK, with six deaths. 85% of patients had not taken antimalarial medication.[21] In a case reported in the British Medical Journal, a woman relied on homeopathic vaccines during a trip to Togo. She developed a severe case of malaria with multiple organ failure, and spent two months in intensive care.[22]
In Queensland, a mother assured doctors that her child was fully immunized, but it turned out that the child had not actually received any of the recommended vaccines. A homeopath had administered some kind of homeopathic “vaccines” and had convinced the mother that her child was fully immunized.[23]
In a survey published in the British Medical Journal, 40% of homeopaths advised against MMR vaccination and only 3% recommended it.[24]
In an Australian court case, a homeopath testified “that homeopathic vaccination was safe and effective, whereas traditional vaccination had short- and long-term risks, including a link to ADHD and autism.”[25]
Testing homeopathy
Testing remedies with provings
Homeopaths think provings are adequate tests. They aren’t. They’re just a collection of anecdotes, and the plural of anecdote is not data. When subjects report “dreams of robbers” during a proving, that is meaningless. What we need to know is whether dreams of robbers are more common in people who have taken that remedy than in people who have taken other remedies or who have not taken any remedy. The process of “provings” is an example of what Richard Feynman dubbed “cargo cult science.” In in World War II, South Seas natives observed planes landing with cargo and they made wooden replicas of planes and control towers, thinking that would magically cause planes to land and supply them with material goods. In cargo cult science, researchers try to imitate the methods of science without understanding them.
Using an appropriate control group.
The importance of using an appropriate control group is vividly illustrated by the experience of surgeons with internal mammary artery ligation, an operation for heart disease. Small incisions were made on either side of the sternum, and the internal mammary arteries were tied off; this was intended to redirect blood flow to the heart, improving circulation in the heart muscle and thereby relieving the pain of angina and reducing the risk of death and disability from heart failure. The operation was devised by an Italian surgeon named Fieschi in 1939; his results were spectacular: three quarters of his patients improved and a third appeared to be cured. The operation was quickly adopted by surgeons all over the world and became very popular. It was “known” to be effective. Then, in the late 1950s, Dr. Leonard Cobb tested the Fieschi operation against a sham surgery control where he made similar incisions in the skin but did nothing more. The results for the real surgery and sham surgery were identical! Surgeons stopped doing that procedure. In his book Taking the Medicine, Druin Burch called it “Medicine’s Beautiful Idea,” the idea that every treatment must be tested, no matter how obviously effective it seems. Scientific testing with proper controls is the only way to determine the truth, and without it we can be fooled into thinking a useless treatment is effective.
Testing homeopathic treatments.
There has been a lot of research on homeopathy, mostly by homeopaths, but few studies have used an appropriate control group.
The Russian hospital ward trial. One of the earliest trials did have appropriate controls, and it was not favorable to homeopathy. The Russian military had been intrigued by preliminary reports of success with homeopathy. In 1829, they ordered Dr. Gigler to supervise a trial in a hospital in St. Petersburg, Russia.[26] Three groups were studied: (1) a hospital ward where a homeopath, Dr. Herrmann, treated all patients with homeopathy, (2) a regular hospital ward where patients were treated with the conventional treatments of the time, and (3) a “no treatment” ward where patients got only supportive care but were subjected to an “innocent deception:” so they wouldn’t realize they were not getting medicine, they were given pills made of breadcrumbs, cocoa, and lactose powder. The “no treatment” group had better outcomes than either of the other two groups, a sad commentary on both homeopathy and the conventional treatment of the time.
Homeopathy in 19th century epidemics. Homeopaths love to point out the success of homeopathy in epidemics of cholera and other infectious diseases during the 19th century.[27] The statistics they cite have been questioned: they were not always based on reliable systematic observations. But it is probably true that patients were more likely to survive the treatment of a homeopath than to survive the treatment of a mainstream doctor of the time. 19th century mainstream treatments did more harm than good; homeopathic treatments did nothing, so they had the advantage. The situation is very different today. Modern science-based medical treatments have been tested and shown to work, so they are likely to be far superior to “doing nothing,” with or without homeopathy.
Homeopathy for childhood diarrhea. In 2003, Jacobs et al. reported on the combined results of three studies on childhood diarrhea in Third World countries. The studies were widely criticized: they were riddled with flaws, and the data from the studies conflicted with each other.[28] Nevertheless, the authors combined the data from all three trials into a meta-analysis and claimed to have found that individualized homeopathic remedies shortened the duration of diarrhea in children – but only by 0.8 days.[29] And a later study by Jacobs was negative: the homeopathic remedies had no effect.[30]
When clinical studies disagree. There have been plenty of positive clinical studies of homeopathy, but there have been plenty of negative studies, too. That’s a common problem in medicine. It’s important to remember that most published research findings are wrong.[31] Small pilot studies are followed by larger, more rigorous studies that often reverse their findings. And there are all kinds of things that can go wrong with a study; sometimes we can identify what went wrong, but often the error is due to some unrecognized confounding factor, to unconscious bias on the part of researchers or subjects, or simply to chance. The commonly used p value of p = 0.05 to measure statistical significance means that if the treatment is ineffective, twenty repetitions of the same trial would likely result in one false positive result. If a treatment is effective, a consistent pattern eventually emerges and experts can arrive at a scientific consensus. If there are conflicting results, a systematic review of the published evidence is done to weigh the evidence on both sides. But a systematic review is only as good as the studies it evaluates, and poor-quality studies result in untrustworthy systematic reviews (GIGO, or garbage in/garbage out).
Systematic reviews
The Lancet. In 1997, a large systematic review was published in the respected journal The Lancet.[32] It looked at 186 trials and concluded that the evidence indicated that homeopathy was more than just a placebo, “However, we found insufficient evidence from these studies that homoeopathy is clearly efficacious for any single clinical condition.” That’s like saying broccoli is good for all people but not for men, women, or children! And in 1999 the authors published a follow-up acknowledging that a number of high-quality studies published after their initial report were negative.[33]
The Cochrane Collaboration. Cochrane is the “gold standard” of systematic reviews. They have found a high risk of bias and false positive results in the available studies and have been unable to find any reliably positive effect of homeopathy.[34]
Cucherat, 2000.[35] This review found “some evidence” that homeopathic treatments are more effective than placebo; however, “the strength of this evidence is low because of the low methodological quality of the trials. Studies of high methodological quality were more likely to be negative than the lower quality studies.” And one of the authors said his review did not reach the conclusion that homeopathy differs from placebo.
Ernst’s systematic review of systematic reviews of homeopathy.[36] Edzard Ernst took it to the next level and did a systematic review of systematic reviews of homeopathy.
He concluded, “the hypothesis that any given homeopathic remedy leads to clinical effects that are relevantly different from placebo or superior to other control interventions for any medical condition, is not supported by evidence from systematic reviews. Until more compelling results are available, homeopathy cannot be viewed as an evidence-based form of therapy.”
The bottom line. A page on RationalWiki lists the scientifically controlled double blind studies that have demonstrated the efficacy of homeopathy. It is a blank page.
Attempts to find a mechanism
Since homeopaths were forced to acknowledge that their remedies contained no molecules of the original substance, they have been desperately trying to find a scientific explanation for how the remedies could still work. Here are some of their arguments:
The remedies are like vaccines. No, they aren’t. Vaccines must contain measurable amounts of antigen, their mechanism of action is based on solid science, and they produce measurable quantities of antibodies. Comparing vaccines to homeopathy is ludicrous.
Hormesis. Hormesis[37] is a documented phenomenon where a low dose of a chemical causes a response opposite to that of a high dose. It is not common: one study suggested it has only been observed in 0.4% of the substances evaluated in toxicology studies.[38] And it can’t possibly apply to homeopathic remedies that contain no dose rather than a low dose.
Water clusters. Water clusters are real, but their existence is transient (on the order of a few thousandths of a trillionth of a second) and it’s hard to imagine how they could carry information about substances they had been in contact with or how that information could affect human health. Edzard Ernst wrote, “The recent observation of solute clusters in highly diluted water has been interpreted by several homeopaths as increasing the plausibility of homeopathy. This novel finding requires independent replication. Furthermore, this observation (if confirmed) does not lend itself to explaining how solute clusters could have any effects on human health. Thus both the clinical evidence and the basic research underpinning homeopathy remain unconvincing.”[39]
Quantum entanglement. People with a poor understanding of quantum physics frequently invoke quantum principles to explain things that quantum principles don’t really explain. There is no evidence to support this hypothesis.
NMR. Studies of nuclear magnetic resonance spectroscopy have found no difference between homeopathic remedies and controls.[40]
Nanoparticles. Dr. Shantaram Kane, a chemical engineer in Mumbai, India, claimed to have found nanoparticles of the parent metal in 200C dilutions of metal-based remedies.[41] It was an uncontrolled study that failed to rule out contamination. He found some kind of experimental artifact and thought he had proved that homeopathy works; he hadn’t.
The Benveniste affair. Jaques Benveniste claimed to have detected biological activity of antibodies after the antibodies had been diluted out. His research was published in Nature with an unusual disclaimer, and with the stipulation that replications of his experiments would be observed by a team of independent investigators.[42] A team of three went to his lab: the editor of Nature (John Maddox, a physicist), a scientific fraud investigator and chemist (Walter Stewart), and the skeptical magician James Randi. Under more rigorous controls, Benveniste’s results could not be replicated. http://www.badscience.net/wp-content/uploads/benveniste02.pdf Additionally, the data Benveniste reported are actually incompatible with homeopathic theory in that subsequent dilutions showed alternating peaks and troughs of activity, whereas the theory predicts that the effect should increase steadily with progressive dilution.
Multiple attempts to replicate Benveniste’s findings failed. The most dramatic test was done on the television program BBC Horizon in the UK. James Randi had offered to give the researchers a million-dollar prize if the test was positive. It was a total failure. http://www.bbc.co.uk/science/horizon/2002/homeopathy.shtml
Benveniste’s reputation continued to suffer. He was the first person to win two of the humorous IgNobel awards, the first for his attempt to prove that water can remember, and the second for claiming “that a [homeopathic] solution’s biological activity can be digitally recorded, stored on a computer hard drive, sent over the Internet as an attached document and transferred to a different water sample at the receiving end.” https://www.nature.com/articles/26831 Benveniste died in 2004, but his name resurfaced five years later in a study by Luc Montagnier.
The Montagnier study. In 2009, using a questionable measuring system devised by Jacques Benveniste, the Nobel-Prize-winning virologist Luc Montagnier claimed to have shown that electromagnetic signals are produced by aqueous nanostructures derived from bacterial DNA.[43] He was hoping to develop a highly sensitive detection system for bacterial infections in humans and animals. The study was flawed, the findings may have been due to noise in the system, and the phenomenon apparently only applied to pathogenic bacteria, not to “good” bacteria, which makes no scientific sense. And it had nothing to do with homeopathy, but that didn’t stop the homeopathic community from laying claim to it, with the headline “Luc Montagnier Foundation Proves Homeopathy Works.”[44]
How a good homeopathy study could be done
Many of the published studies of homeopathy are flawed and biased. Some didn’t even use a credible control group. If homeopaths were rigorous scientists, what might they have done?
For provings, they could have randomized subjects into four groups: one would get the remedy being tested, one would get a different remedy, one would get water that had been diluted and succussed in the same manner as the remedies, and a final group would get nothing. Similar explanations and instructions would be given to all, and they would all report symptoms in the same way. Except for the last group, no subjects would be able to guess which group they were in, and the researchers who were dispensing the remedies and collecting the symptom data wouldn’t know either. A statistician would have to be consulted to determine how many subjects should be in each group, and what statistical tests should be applied to determine if there were any significant differences between the groups. If significant differences were found, a second trial could be done on a different group of subjects to see if they reported similar symptoms. Only replicable symptoms that could be directly linked to the test remedy would be considered for addition to the repertory.
Individual homeopathic remedies could be tested exactly as prescription drugs are tested. In a randomized, placebo-controlled, double-blind trial, subjects would either get the test remedy or a placebo preparation, and neither the subjects nor the researchers would know which they got. A no-treatment group would be helpful for comparison.
Homeopaths frequently claim that it’s not fair to test homeopathy on the same basis as prescription drugs. In classical homeopathy, the homeopath spends time with the patient, prescribes individualized remedies, and changes the remedies as needed on follow-up visits. They say that their individualized treatments can’t be evaluated by a randomized, double-blind, placebo-controlled study. But they can; it just requires a more sophisticated design. There can be no double standard; homeopaths can’t claim special treatment and exemption from the standard scientific method.
There are ethical considerations. Studies involving human subjects must be approved by an institutional review board (IRB) to protect the rights and welfare of participants. Medical ethics requires clinical equipoise. Clinical equipoise is the assumption that there is not one ‘better’ intervention present (for either the control or experimental group) during the design of a randomized controlled trial. A true state of equipoise exists when one has no good basis for a choice between two or more care options.[45] If there is a proven effective medical treatment, it would be unethical to deny that treatment to patients and give them only unproven homeopathic remedies. A benign, self-limiting condition could be chosen, like infant colic or the common cold. There is no cure for the common cold, only measures to reduce symptoms; a cold will run its course in the same length of time with or without treatment. Patients could be randomly assigned to treatment by a homeopath or an MD, with whatever treatment the provider chose to give them, with a no-treatment group for comparison, and the duration of cold symptoms could be tracked.
That would be a test of whether the encounter with a classical homeopath was effective. Another thing to test is whether it makes any difference which remedy the patient is given. The homeopath could prescribe whatever remedy or succession of remedies he thought was indicated. The patient would take the prescriptions to be filled by a second person. That second person would dispense either the prescribed remedy or a placebo remedy, depending on which group the patient was randomized to. A third person would be responsible for the randomization and would prepare and label the remedies in such a way that the person doing the dispensing couldn’t tell whether he was dispensing the remedy or the placebo.
Homeopaths could have done more rigorous research but they have not wanted to. In essence, homeopathy is based on belief rather than on scientific evidence. When good research has been done, the more rigorous the study, the less positive the results. Negative studies have had no impact on the beliefs of homeopaths.
More rigorous good double-blind studies could be done, but at this point they shouldn’t be done. Homeopathy has had over two centuries to produce evidence that would convince the scientific community that it works, and it has been unable to do so. All the published research is compatible with exactly what would be expected from studying an ineffective treatment. There isn’t enough evidence for homeopathy to justify spending any more of our scarce research funds on such an unpromising topic.
Criticism of homeopathy
Homeopathy was masterfully debunked in 1842, during Hahnemann’s lifetime, by Oliver Wendell Holmes, in his classic Homeopathy and Its Kindred Delusions.[46] Scientific medicine had not yet come into its own, but Holmes had excellent critical thinking skills. He knew that testimonials are not facts and he understood how easily people can be fooled. He dismissed the main homeopathic doctrines of like cures like, infinitesimals, and miasms as delusional beliefs rather than facts. He showed that homeopathy had already failed a number of simple tests. He said there was no point in further testing, since experiments disproving delusional medical practices never accomplish anything: they are always just explained away by true believers. He showed that published case reports of homeopathic cures were nothing but meaningless propaganda. He expected homeopathy to disappear, and would have been very disappointed to know it would still be with us in the 21st century.
More recently, homeopathy has had a number of other outspoken critics. Jay Shelton wrote the excellent book Homeopathy: How It Really Works, concluding that it “works” for reasons other than the remedies themselves, as a placebo. In the process, he explains in detail how science operates to rule out false attributions of cause and effect. Edzard Ernst was trained as a homeopath but he soon became the world’s first Professor of Complementary Medicine and dedicated his career to investigating the scientific evidence for alternative medicines. His book Homeopathy: The Undiluted Facts provides a fair, balanced, comprehensive critique of homeopathy. It says everything worth saying. On Stephen Barrett’s Quackwatch website there is a whole subsection Homeowatch[47] with extensive links to reference material. Homeopathy has been called “the ultimate fraud,” and “delusions about dilutions.” The Science-Based Medicine website maintains an extensive reference section on homeopathy, covering the key research and listing the dozens of SBM articles that have been written about it.[48]
Several major medical organizations have issued statements that “there is no good-quality evidence that homeopathy is effective as a treatment for any health condition.” Among them are the UK’s National Health Service, the American Medical Association, the Federation of American Societies for Experimental Biology (FASEB), and the National Health and Medical Research Council of Australia. A 2011 report from the Swiss government was supportive of homeopathy, but it was found to be biased and scientifically suspect.[49]
What’s the harm?
Some people argue that placebos are harmless and can make people feel better. They say, “Even if homeopathy is just a placebo, why not use it?” There are three good reasons not to:
- It can cause direct harm, especially to children. The American Association of Poison Control Centers reported that in 2012 there were 10,311 cases of poison exposure from homeopathic agents, with 8788 in children age 5 or younger, and with 897 requiring treatment in a health care facility.[50] And as mentioned above, the FDA issued a warning about homeopathic teething remedies causing belladonna poisoning in infants.
- It can cause indirect harm by delaying or replacing effective medical treatment. The What’s the Harm website[51] lists many such cases. Isabella Denley was just 13 months old when she died after her parents substituted homeopathic remedies for the anti-convulsant medications prescribed by her neurologist. 16-year-old Kate Ross of Nevada had ulcerative colitis; surgery was recommended to remove her colon, but her mother chose homeopathic treatments instead. She went from 90 pounds to 50 pounds and nearly died when her colon perforated, but survived when child services intervened and her mother finally agreed to lifesaving surgery.
- Placebos are never a good idea. It is unethical for a doctor to knowingly prescribe a placebo to patients and lie to them, making them think it is an effective treatment; and if patients discover the deception, they will no longer be able to trust the doctor. Patients who self-treat with homeopathic remedies for benign, self-limiting conditions can be fooled into thinking homeopathy works and when they later develop a serious disease they are more likely to try homeopathy instead of medical treatments that have been proven effective.
Why people believe homeopathy works
Patients and homeopaths alike have become convinced that homeopathy works because they have seen it work. Patients treated with homeopathy got better. Personal experience is very compelling. Because of the way our minds evolved, we tend to find stories more convincing than studies, testimonials more convincing than scientific tests, personal experience more convincing than scientific evidence. But those experiences and stories can very easily lead us astray.
It is all too easy to succumb to the post hoc ergo propter hoc fallacy, “after that, therefore because of that,” the idea that when Y follows X, X must have caused Y. The rooster’s crowing is followed by sunrise, but the rooster doesn’t cause the sun to come up. Yet when a symptom disappears after a treatment, it seems intuitively obvious that the treatment must have cured the symptom. That may not be true. There are many other possible explanations.
There are many ways patients can be deceived or can deceive themselves. The late Barry Beyerstein wrote a classic article about this, titled “Why Bogus Therapies Seem to Work.”[52]
- Natural healing. Many illnesses get better and go away on their own: the common cold is a prime example. And even before antibiotics, some patients with pneumonia recovered.
- Placebo effects. Placebos don’t have objective effects; they won’t make broken bones heal faster or improve survival rates in cancer. But the caring attention of a health care provider and the suggestion, expectation, and reassurance invoked by the treatment encounter can easily result in improvement of subjective symptoms like pain, nausea, and anxiety.
- Regression to the mean. Many diseases are cyclical. If treatment happens to coincide with a downturn in the cycle, the treatment may falsely get the credit for the improvement.
- Spontaneous remission. Even advanced cancers have been known to undergo spontaneous remission. We don’t know why it happens, but it may happen more often than we realize.
- Cessation of harmful or unpleasant treatments. If you are suffering side effects from a prescription drug and the homeopath gets you to stop taking it and use his remedies instead, of course you will feel better. Because of stopping the drug, not because of starting the homeopathic remedy.
- Lifestyle-assisted healing. An expectant attitude may lead to better compliance with healthy lifestyle measures. The patient may stop smoking, start exercising, eat a healthier diet, and make other beneficial changes.
- Learned responses. Just as Pavlov’s dogs became conditioned to salivate when the dinner bell rang, people can become conditioned to expect relief of symptoms with a pill. If they happened to get better spontaneously after taking a homeopathic remedy, they may expect it to work next time for the next problem.
- Unrecognized factors. Maybe something else happened in the patient’s life at the same time that affected the illness but went unnoticed. Jay Shelton called it the spaghetti effect: near the time of treatment, maybe the patient changed his brand of spaghetti sauce and the new sauce contained some herb or amino acid that was a cure for the ailment.
- The patient actually has another, milder, self-limiting condition that will resolve on its own.
- Incorrect prognosis. If a patient thinks his doctor has given him six months to live and he survives much longer, it may be that the doctor’s prognosis was wrong, or the patient may have misremembered or misinterpreted what the doctor said.
- Different perceptions of internal vs. external reality. There is an external physical, material reality that we all share, but a person’s internal perceptions and feelings may create a different internal reality.
- The disease never existed in the first place. The “worried well” are healthy but convinced they are sick. Some people who are convinced they were cured of cancer never had a biopsy and were never actually diagnosed with cancer.
- Psychosomatic symptoms. In a phenomenon known as somatization, psychological distress is expressed in the language of physical symptoms. The physical symptoms tend to subside if the psychological distress abates.
- Psychological healing and improved mood. Anything that reduces the emotional component of pain will make the pain more bearable. The patient’s mood may improve with an upbeat, charismatic provider; he may feel someone has truly listened to him, understands what he is going through, cares deeply about him, and has promised he will get better soon. The suffering may be reduced without the underlying condition having improved in any way.
- Psychological distortion of reality. Strong belief can lead to distortion of reality. People who have invested time and money in a treatment don’t want to admit it has been a waste. They are strongly motivated to find benefit in the treatment. People may selectively recall successes and downplay or explain away the failures. They may misremember how they felt before treatment.
- The norm of reciprocity. People tend to respond in kind when someone does them a good turn. They want to please the therapist.
- Voltaire said, “The art of medicine consists in amusing the patient while nature cures the disease.” Ineffective treatments serve to keep the patient entertained while the disease runs its course.
There are so many ways we can get it wrong! And there is only one way we can get it right: controlled scientific testing.
Conclusion
Homeopathy is a system of alternative medicine that was conceived by a single misguided individual in a pre-scientific era. It is based on imagination, not reality; on stories, not science. It not only doesn’t work, it couldn’t possibly work. Its practices and principles are laughable. Some people have been fooled into thinking it works because of factors like suggestion, placebo effects, the influence of the doctor/patient interaction, regression to the mean, the natural course of the disease, and other sources of human error. The homeopathic remedy itself is irrelevant. After two centuries of trying, homeopaths have not been able to show any credible evidence that they are doing anything but prescribing placebos. The persistence of homeopathy in the 21st century is an anachronistic anomaly.
[1] http://edzardernst.com/2015/12/the-prime-assumption-of-homeopathy-is-based-on-a-misunderstanding/
[2] http://www.oxford-homeopathy.org.uk/homeopathy-origins-history.htm
[3] http://www.oxford-homeopathy.org.uk/homeopathy-origins-history.htm
[4] http://archive.carnegiefoundation.org/pdfs/elibrary/Carnegie_Flexner_Report.pdf
[5] https://sciencebasedmedicine.org/homeopathy-first-aid-kits/
[6] https://www.ftc.gov/news-events/press-releases/2016/11/ftc-issues-enforcement-policy-statement-regarding-marketing
[7] http://www.telegraph.co.uk/news/uknews/prince-charles/10433939/Prince-Charles-and-homeopathy-crank-or-revolutionary.html
[8] https://en.wikipedia.org/wiki/NHS_homeopathic_hospitals
[9] https://sciencebasedmedicine.org/good-thinking-societys-successful-challenge-to-nhs-homeopathy/
[11] https://hpathy.com/abc-homeopathy/homeopathy-principles/
[12] http://www.cnn.com/2017/01/27/health/homeopathic-teething-belladonna-fda/index.html
[13] https://nyhomeopathy.com/provings/musca-domestica/
[14] http://www.homeopathycenter.org/homeopathy-today/thought-behind-action-miasms-psora-syphilis-sycosis
[15] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2505097/pdf/jcca00005-0006.pdf
[16] http://edzardernst.com/2013/03/the-four-types-of-homeopaths-would-hahnemann-approve/
[17] http://www.bhia.org/holistic/electro-homeopathy.htm
[18] https://books.google.com/books?id=KZZpAgAAQBAJ&pg=PA32&lpg=PA32&dq=Electricitas+200C+car&source=bl&ots=HokUBD4m2Y&sig=Nqx7FNsOSPyYV27d0oNyzlQeeXo&hl=en&sa=X&ved=0ahUKEwiwysDdocvXAhVpzlQKHWSaAlUQ6AEIKDAA#v=onepage&q=Electricitas%20200C%20car&f=false
[19] http://www.bcmj.org/council-health-promotion/health-canada-licenses-homeopathic-vaccines
[20] http://www.badscience.net/2006/09/newsnightsense-about-science-malaria-homeopathy-sting-the-transcripts/
[21] https://travelhealthpro.org.uk/news/6/malaria-imported-into-the-united-kingdom-2015
[22] http://www.bmj.com/content/321/7271/1288.2.full
[23] http://www.abc.net.au/news/2013-08-03/queensland-health-raises-alarm-over-homeopath27s-alleged-immun/4863170
[24] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1124112/
[25] http://www.smh.com.au/national/health/homeopathy-regime-is-rejected-as-judge-tells-parents-to-immunise-child-20121127-2a5uo.html
[26] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1484568/
[27] http://www.homeopathycenter.org/treatment-epidemics-homeopathy-history
[28] https://sciencebasedmedicine.org/getting-it-on-with-homeopathy/
[29] https://www.ncbi.nlm.nih.gov/pubmed/12634583
[30] https://www.ncbi.nlm.nih.gov/pubmed/17034278
[31] http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124
[32] http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(97)02293-9/abstract
[33] https://www.ncbi.nlm.nih.gov/pubmed/10391656
[34] http://www.cochrane.org/CD000353/AIRWAYS_homeopathy-for-chronic-asthma
[35] https://www.ncbi.nlm.nih.gov/pubmed/10853874
[36] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1874503/
[37] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2248601/
[38] https://academic.oup.com/toxsci/article/62/2/330/1663654
[39] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1874503/
[40] https://www.ncbi.nlm.nih.gov/pubmed/11212083
[41] https://sciencebasedmedicine.org/homeopathy-and-nanoparticles/
[42] https://www.ncbi.nlm.nih.gov/pubmed/2455231
[43] https://www.ncbi.nlm.nih.gov/pubmed/20640822
[44] http://homeopathyworldcommunity.ning.com/group/latesthomeopathynews/forum/topics/luc-montagnier-foundation
[45] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3172958/
[46] https://www.quackwatch.org/01QuackeryRelatedTopics/holmes.html
[47] https://www.homeowatch.org
[48] https://sciencebasedmedicine.org/reference/homeopathy/
[49] https://sciencebasedmedicine.org/the-swiss-report-on-homeopathy/
[50] https://aapcc.s3.amazonaws.com/pdfs/annual_reports/2012_NPDS_Annual_Report.pdf
[52] https://www.csicop.org/si/show/why_bogus_therapies_seem_to_work
This article was commissioned by the James Randi Educational Foundation.