Homeopathy 
i/ˌhoʊmiˈɒpəθi/ (also spelled
homoeopathy or
homœopathy; from the Greek
hómoios- ὅμοιος- "like-" +
páthos πάθος "suffering") is a form of
alternative medicineoriginated by
Samuel Hahnemann (1755–1843), based on the idea that a substance that causes the symptoms of a disease in healthy people will cure that disease in sick people.
[1]This axiom is known as "the law of similars" or "like cures like". Scientific research has found homeopathic remedies ineffective and their postulated mechanisms of action implausible.
[2][3][4] Within the
medical community homeopathy is generally considered
quackery.
[5]
In addition to symptoms, homeopaths consider a patient's physical and psychological state and life history,
[6] before consulting homeopathic reference books known as "repertories" to select a
"remedy" based on the "totality of symptoms" as well as personal traits. Homeopathic remedies are prepared by
serial dilution of a chosen substance in alcohol or distilled water, followed by forceful striking on an elastic body, called "succussion". Each dilution followed by succussion is supposed to increase the remedy's potency. Homeopaths call this process "potentization". Dilution usually continues well past the point where none of the original substance remains.
[7]
The low concentrations of homeopathic remedies, often lacking even a single
molecule of the diluted substance,
[8] lead to an objection that has dogged homeopathy since the 19th century: how, then, can the substance have any effect? Modern advocates of homeopathy have suggested that "
water has a memory"—that during mixing and succussion, the substance leaves an enduring effect on the water, perhaps a "vibration", and this produces an effect on the patient. However, nothing like water memory has ever been found in chemistry or physics.
[9][10] Furthermore, the claims of homeopathy contradict
pharmacological science, which shows that
higher doses of an active ingredient exert stronger effects.
Homeopathic remedies have been the subject of numerous
clinical trials, which test the possibility that they may be effective through some mechanism unknown to science. While some individual studies have positive results,
[11][12] systematic reviews of published trials have failed to demonstrate efficacy.
[4][13][14][15][16] Because of the extremely high dilutions, most homeopathic remedies are, at least, harmless. However, patients who choose to use homeopathy rather than normal medicine risk missing timely diagnosis and effective treatment of serious conditions.
[17] The
regulation and prevalence of homeopathy vary greatly from country to country.
[18]
pathology and a strong link to conventional medicine, while those favoring high dilutions emphasised vital force, miasms and a spiritual interpretation of disease.[62][63] Some products with such relatively lower dilutions continue to be sold, but like their counterparts, they have not been conclusively demonstrated to have any effect beyond that of a placebo.[64][65]
Provings
Hahnemann experimented on himself and others for several years before using remedies on patients. His experiments did not initially consist of giving remedies to the sick, because he thought that the most similar remedy, by virtue of its ability to induce symptoms similar to the disease itself, would make it impossible to determine which symptoms came from the remedy and which from the disease itself. Therefore, sick people were excluded from these experiments. The method used for determining which remedies were suitable for specific diseases was called "proving", after the original German word
Prüfung, meaning "test". A homeopathic proving is the method by which the profile of a homeopathic remedy is determined.
[66]
At first Hahnemann used undiluted doses for provings, but he later advocated provings with remedies at a 30C dilution,
[48] and most modern provings are carried out using ultradilute remedies in which it is highly unlikely that any of the original molecules remain.
[67]During the proving process, Hahnemann administered remedies to healthy volunteers, and the resulting symptoms were compiled by observers into a "drug picture". The volunteers were observed for months at a time and made to keep extensive journals detailing all of their symptoms at specific times throughout the day. They were forbidden from consuming coffee, tea, spices, or wine for the duration of the experiment; playing chess was also prohibited because Hahnemann considered it to be "too exciting", though they were allowed to drink beer and encouraged to exercise in moderation. After the experiments were over, Hahnemann made the volunteers take an oath swearing that what they reported in their journals was the truth, at which time he would interrogate them extensively concerning their symptoms.
Provings have been described as important in the development of the
clinical trial, due to their early use of simple control groups, systematic and quantitative procedures, and some of the first application of
statistics in medicine.
[68] The lengthy records of self-experimentation by homeopaths have occasionally proven useful in the development of modern drugs: For example, evidence that
nitroglycerin might be useful as a treatment for
angina was discovered by looking through homeopathic provings, though homeopaths themselves never used it for that purpose at that time.
[69] The first recorded provings were published by Hahnemann in his 1796
Essay on a New Principle.
[70] His
Fragmenta de Viribus (1805)
[71] contained the results of 27 provings, and his 1810
Materia Medica Puracontained 65.
[72] For
James Tyler Kent's 1905
Lectures on Homoeopathic Materia Medica, 217 remedies underwent provings and newer substances are continually added to contemporary versions.
Though the proving process has superficial similarities with clinical trials, it is fundamentally different in that the process is subjective, not blinded, and modern provings are unlikely to use pharmacologically active levels of the substance under proving.
[73] As early as 1842, Holmes noted the provings were impossibly vague, and the purported effect was not repeatable among different subjects.
[74]
Physical, mental, and emotional state examination; Repertories
Homeopathic repertory by James Tyler Kent
Homeopaths generally begin with detailed examinations of their patients' histories, including questions regarding their physical, mental and emotional states, their life circumstances and any physical or emotional illnesses. The homeopath then attempts to translate this information into a complex formula of mental and physical symptoms, including likes, dislikes, innate predispositions and even body type.
[75]
From these symptoms, the homeopath chooses how to treat the patient. A compilation of reports of many homeopathic provings, supplemented with clinical data, is known as a "homeopathic materia medica". But because a practitioner first needs to explore the remedies for a particular symptom rather than looking up the symptoms for a particular remedy, the "homeopathic repertory", which is an index of symptoms, lists after each symptom those remedies that are associated with it. Repertories are often very extensive and may include data extracted from multiple sources of materia medica. There is often lively debate among compilers of repertories and practitioners over the veracity of a particular inclusion.
The first symptomatic index of the homeopathic
materia medica was arranged by Hahnemann. Soon after, one of his students,
Clemens von Bönninghausen, created the
Therapeutic Pocket Book, another homeopathic repertory.
[76] The first such homeopathic repertory was Georg Jahr's
Symptomenkodex, published in German (1835), which was then first translated to English (1838) by Constantine Hering as the
Repertory to the more Characteristic Symptoms of Materia Medica. This version was less focused on disease categories and would be the forerunner to Kent's later works.
[35][77] It consisted of three large volumes. Such repertories increased in size and detail as time progressed.
Some diversity in approaches to treatments exists among homeopaths. "Classical homeopathy" generally involves detailed examinations of a patient's history and infrequent doses of a single remedy as the patient is monitored for improvements in symptoms, while "clinical homeopathy" involves combinations of remedies to address the various symptoms of an illness.
[78]
Homeopathic pills
Homeopathic pills are made from an inert substance (often sugars, typically lactose), upon which a drop of liquid homeopathic preparation is placed.
[8][79]
"Active" ingredients
The list of ingredients seen on remedies may confuse consumers into believing the product actually contains those ingredients. According to normal homeopathic practice, remedies are prepared starting with
active ingredients that are often serially diluted to the point where the finished product no longer contains any biologically "active ingredients" as that term is normally defined.
James Randi and the
10:23 campaign groups have demonstrated the lack of active ingredients in homeopathic products by taking large overdoses.
[80] None of the hundreds of demonstrators in the UK, Australia, New Zealand, Canada and the US were injured and "no one was cured of anything, either".
[81]
While the lack of active compounds is noted in most homeopathic products, there are some exceptions such as
Zicam Cold Remedy, which is marketed as an "unapproved homeopathic" product.
[82] It contains a number of highly diluted ingredients that are listed as "inactive ingredients" on the label. Some of the homeopathic ingredients used in the preparation of Zicam are galphimia glauca,
[83]histamine dihydrochloride (homeopathic name,
histaminum hydrochloricum),
[84] luffa operculata,
[85] and
sulfur. Although the product is marked "homeopathic", it does contain two ingredients that are only "slightly" diluted:
zinc acetate (2X = 1/100 dilution) and
zinc gluconate (1X = 1/10 dilution),
[82] which means both are present in a concentration that contains biologically active ingredients. In fact, they are strong enough to have caused some people to lose their sense of smell,
[86] a condition termed
anosmia. This illustrates why taking a product marked "homeopathic", especially an
overdose,
[80] can still be dangerous because it may contain biologically active ingredients, though as discussed previously, most homeopathic preparations contain no active ingredients. Because the manufacturers of Zicam label it as a homeopathic product (despite the relatively high concentrations of active ingredients), it is exempted from FDA regulation by the Dietary Supplement Health and Education Act of 1994 (DSHEA).
Related practices
Isopathy
Isopathy is a therapy derived from homeopathy invented by Johann Joseph Wilhelm Lux in the 1830s. Isopathy differs from homeopathy in general in that the remedies, known as "nosodes", are made up either from things that cause the
disease or from products of the disease, such as
pus.
[35][87] Many so-called "homeopathic vaccines" are a form of isopathy.
[88]
Flower remedies
Flower remedies can be produced by placing flowers in water and exposing them to sunlight. The most famous of these are the
Bach flower remedies, which were developed by the physician and homeopath
Edward Bach. Although the proponents of these remedies share homeopathy's vitalist world-view and the remedies are claimed to act through the same hypothetical "vital force" as homeopathy, the method of preparation is different. Bach flower remedies are prepared in "gentler" ways such as placing flowers in bowls of sunlit water, and the remedies are not succussed.
[89] There is no convincing scientific or clinical evidence for flower remedies being effective.
[90]
Veterinary use
The idea of using homeopathy as a treatment for other animals, termed "veterinary homeopathy", dates back to the inception of homeopathy; Hahnemann himself wrote and spoke of the use of homeopathy in animals other than humans.
[91] The FDA has not approved homeopathic products as veterinary medicine in the U.S. In the UK,
veterinary surgeons who use homeopathy belong to the
Faculty of Homeopathy and/or to the British Association of Homeopathic Veterinary Surgeons. Animals may be treated only by qualified veterinary surgeons in the UK and some other countries. Internationally, the body that supports and represents homeopathic veterinarians is the International Association for Veterinary Homeopathy. The use of homeopathy in veterinary medicine is controversial; the little existing research on the subject is not of a high enough scientific standard to provide reliable data on efficacy.
[92] Other studies have also found that giving animals placebos can play active roles in influencing pet owners to believe in the effectiveness of the treatment when none exists.
[92]
Electrohomeopathy
