Homeopathy or homoeopathy is a
pseudoscientific
Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable cl ...
system of
alternative medicine
Alternative medicine refers to practices that aim to achieve the healing effects of conventional medicine, but that typically lack biological plausibility, testability, repeatability, or supporting evidence of effectiveness. Such practices are ...
. It was conceived in 1796 by the German physician
Samuel Hahnemann
Christian Friedrich Samuel Hahnemann ( , ; 10 April 1755 – 2 July 1843) was a German physician, best known for creating the pseudoscientific system of alternative medicine called homeopathy.
Early life
Christian Friedrich Samuel Hahnemann w ...
. Its practitioners, called homeopaths or homeopathic physicians, believe that a substance that causes symptoms of a disease in healthy people can cure similar symptoms in sick people; this doctrine is called ''
similia similibus curentur'', or "like cures like".
Homeopathic preparations are termed ''remedies'' and are made using
homeopathic dilution
In homeopathy, homeopathic dilution (known by practitioners as "dynamisation" or "potentisation") is a process in which a substance is diluted with alcohol or distilled water and then vigorously shaken in a process called "succussion". Insoluble ...
. In this process, the selected substance is repeatedly diluted until the final product is chemically indistinguishable from the
diluent
A diluent (also referred to as a filler, dilutant or thinner) is a diluting agent. Certain fluids are too viscous to be pumped easily or too dense to flow from one particular point to the other. This can be troublesome, because it might not be ...
. Often not even a single molecule of the original substance can be expected to remain in the product. Between each dilution homeopaths may hit and/or shake the product, claiming this makes the diluent "remember" the original substance after its removal. Practitioners claim that such preparations, upon oral intake, can treat or cure disease.
All relevant scientific knowledge about physics, chemistry, biochemistry and biology contradicts homeopathy. Homeopathic remedies are typically
biochemically inert, and have no effect on any known disease.
Its theory of disease, centered around principles Hahnemann termed
miasms, is inconsistent with subsequent identification of viruses and bacteria as
causes of disease. Clinical trials have been conducted and generally demonstrated no objective effect from homeopathic preparations.
The fundamental
implausibility of homeopathy as well as a lack of demonstrable effectiveness has led to it being characterized within the scientific and medical communities as
quackery
Quackery, often synonymous with health fraud, is the promotion of fraudulent or Ignorance, ignorant medicine, medical practices. A quack is a "fraudulent or ignorant pretender to medical skill" or "a person who pretends, professionally or public ...
and
fraud
In law, fraud is intent (law), intentional deception to deprive a victim of a legal right or to gain from a victim unlawfully or unfairly. Fraud can violate Civil law (common law), civil law (e.g., a fraud victim may sue the fraud perpetrato ...
.
Homeopathy achieved its greatest popularity in the 19th century. It was introduced to the United States in 1825, and the first American homeopathic school opened in 1835. Throughout the 19th century, dozens of homeopathic institutions appeared in Europe and the United States. During this period, homeopathy was able to appear relatively successful, as other forms of treatment could be harmful and ineffective. By the end of the century the practice began to wane, with the last exclusively homeopathic medical school in the United States closing in 1920. During the 1970s, homeopathy made a significant comeback, with sales of some homeopathic products increasing tenfold. The trend corresponded with the rise of the
New Age movement
New Age is a range of spiritual or religious practices and beliefs that rapidly grew in Western society during the early 1970s. Its highly eclectic and unsystematic structure makes a precise definition difficult. Although many scholars consid ...
, and may be in part due to
chemophobia
Chemophobia (or chemphobia or chemonoia) is an aversion to or prejudice against chemicals or chemistry. The phenomenon has been ascribed both to a reasonable concern over the potential adverse effects of synthetic chemicals, and to an irrational ...
, an irrational aversion to synthetic chemicals, and the longer consultation times homeopathic practitioners provided.
In the 21st century, a series of
meta-analyses
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...
have shown that the therapeutic claims of homeopathy lack scientific justification. As a result, national and international bodies have recommended the withdrawal of government funding for homeopathy in healthcare. National bodies from Australia, the United Kingdom, Switzerland and France, as well as the
European Academies' Science Advisory Council
The European Academies' Science Advisory Council (EASAC) is a regional association of National Academies of science. Its members are 25 National Science Academies of the Member States of the European Union (EU), and the National Science Academies ...
and the
Russian Academy of Sciences
The Russian Academy of Sciences (RAS; ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across the Russian Federation; and additional scientific and social units such ...
have all concluded that homeopathy is ineffective, and recommended against the practice receiving any further funding.
The
National Health Service in England
The National Health Service (NHS) is the Publicly funded health care, publicly funded healthcare system in England, and one of the four National Health Service systems in the United Kingdom. It is the second largest single-payer healthcare sy ...
no longer provides funding for homeopathic remedies and asked the
Department of Health to add homeopathic remedies to the list of forbidden prescription items.
France removed funding in 2021,
while Spain has also announced moves to ban homeopathy and other pseudotherapies from health centers.
History
Homeopathy was created in 1796 by
Samuel Hahnemann
Christian Friedrich Samuel Hahnemann ( , ; 10 April 1755 – 2 July 1843) was a German physician, best known for creating the pseudoscientific system of alternative medicine called homeopathy.
Early life
Christian Friedrich Samuel Hahnemann w ...
. Hahnemann rejected the mainstream medicine of the late 18th century as irrational and inadvisable, because it was largely ineffective and often harmful.
[
] He advocated the use of single drugs at lower doses and promoted an immaterial,
vitalistic view of how living organisms function.
The term ''homeopathy'' was coined by Hahnemann and first appeared in print in 1807. He also coined the expression "
allopathic medicine
Allopathic medicine, or allopathy, is an archaic and derogatory label originally used by 19th-century homeopaths to describe heroic medicine, the precursor of modern evidence-based medicine. Citing: ''Gale Encyclopedia of Medicine'' (2008) and ...
", which was used to pejoratively refer to traditional Western medicine.
Concept
Hahnemann conceived of homeopathy while translating a medical treatise by the Scottish physician and chemist
William Cullen into German. Being sceptical of Cullen's theory that
cinchona
''Cinchona'' (pronounced or ) is a genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. All are native to the Tropical Andes, tropical Andean forests of western South America. A few species are ...
cured
malaria
Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...
because it was bitter, Hahnemann ingested some bark specifically to investigate what would happen. He experienced fever, shivering and
joint pain
Arthralgia () literally means 'joint pain'. Specifically, arthralgia is a symptom of injury, infection, illness (in particular arthritis), or an allergic reaction to medication
Medication (also called medicament, medicine, pharmaceutic ...
: symptoms similar to those of malaria itself. From this, Hahnemann came to believe that all effective drugs produce symptoms in healthy individuals similar to those of the diseases that they treat.
This led to the name ''"homeopathy"'', which comes from the ''hómoios'', "-like" and ''páthos'', "suffering".
The doctrine that those drugs are effective which produce symptoms similar to the symptoms caused by the diseases they treat, called "the law of similars", was expressed by Hahnemann with the Latin phrase ''
similia similibus curentur'', or "like cures like".
Hahnemann's law of similars is unproven and does not derive from the
scientific method
The scientific method is an Empirical evidence, empirical method for acquiring knowledge that has been referred to while doing science since at least the 17th century. Historically, it was developed through the centuries from the ancient and ...
.
An account of the effects of eating cinchona bark noted by
Oliver Wendell Holmes, published in 1861, failed to reproduce the symptoms Hahnemann reported.
Subsequent scientific work showed that cinchona cures malaria because it contains
quinine
Quinine is a medication used to treat malaria and babesiosis. This includes the treatment of malaria due to ''Plasmodium falciparum'' that is resistant to chloroquine when artesunate is not available. While sometimes used for nocturnal leg ...
, which kills the ''
Plasmodium falciparum
''Plasmodium falciparum'' is a Unicellular organism, unicellular protozoan parasite of humans and is the deadliest species of ''Plasmodium'' that causes malaria in humans. The parasite is transmitted through the bite of a female ''Anopheles'' mos ...
'' parasite that causes the disease; the mechanism of action is unrelated to Hahnemann's ideas.
Provings
Hahnemann began to test what effects various substances may produce in humans, a procedure later called "homeopathic proving". These tests required subjects to test the effects of ingesting substances by recording all their symptoms as well as the ancillary conditions under which they appeared.
He published a collection of provings in 1805, and a second collection of 65 preparations appeared in his book, ''Materia Medica Pura'' (1810).
As Hahnemann believed that large doses of drugs that caused similar symptoms would only aggravate illness, he advocated for extreme dilutions. A technique was devised for making dilutions that Hahnemann claimed would preserve the substance's therapeutic properties while removing its harmful effects.
Hahnemann believed that this process enhanced "the spirit-like medicinal powers of the crude substances".
[.
] He gathered and published an overview of his new medical system in his book, ''
The Organon of the Healing Art'' (1810), with a sixth edition published in 1921 that homeopaths still use today.
[
]
Miasms and disease
In the ''Organon'', Hahnemann introduced the concept of "miasms" as the "infectious principles" underlying chronic disease
and as "peculiar morbid derangement
of vital force".
Hahnemann associated each miasm with specific diseases, and thought that initial exposure to miasms causes local symptoms, such as skin or venereal diseases. His assertion was that if these symptoms were suppressed by medication, the cause went deeper and began to manifest itself as diseases of the internal organs.
Homeopathy maintains that treating diseases by directly
alleviating their symptoms, as is sometimes done in conventional medicine, is ineffective because all "disease can generally be traced to some latent, deep-seated, underlying chronic, or inherited tendency". The underlying imputed miasm still remains, and deep-seated ailments can be corrected only by removing the deeper disturbance of the vital force.
[
]
Hahnemann's
hypotheses
A hypothesis (: hypotheses) is a proposed explanation for a phenomenon. A scientific method, scientific hypothesis must be based on observations and make a testable and reproducible prediction about reality, in a process beginning with an educ ...
for miasms originally presented only three local symptoms: psora (the itch),
syphilis
Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms depend on the stage it presents: primary, secondary, latent syphilis, latent or tertiary. The prim ...
(venereal disease) or
sycosis (fig-wart disease). Of these the most important was ''psora'', described as being related to any itching diseases of the skin and was claimed to be the foundation of many further disease conditions. Hahnemann believed it to be the cause of such diseases as
epilepsy
Epilepsy is a group of Non-communicable disease, non-communicable Neurological disorder, neurological disorders characterized by a tendency for recurrent, unprovoked Seizure, seizures. A seizure is a sudden burst of abnormal electrical activit ...
,
cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
,
jaundice
Jaundice, also known as icterus, is a yellowish or, less frequently, greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving ...
,
deafness
Deafness has varying definitions in cultural and medical contexts. In medical contexts, the meaning of deafness is hearing loss that precludes a person from understanding spoken language, an audiological condition. In this context it is writte ...
, and
cataracts
A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision of the eye. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colours, blurry or double vision, halos around ligh ...
.
[
] Since Hahnemann's time, other miasms have been proposed, some replacing illnesses previously attributed to the psora, including
tuberculosis
Tuberculosis (TB), also known colloquially as the "white death", or historically as consumption, is a contagious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can al ...
and
cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
miasms.
[
]
Hahnemann's miasm theory remains disputed and controversial within homeopathy even in modern times. The theory of miasms has been criticized as an explanation developed to preserve the system of homeopathy in the face of treatment failures, and for being inadequate to cover the many hundreds of sorts of diseases, as well as for failing to explain disease predispositions, as well as
genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian ...
, environmental factors, and the unique disease history of each patient.
19th century: rise to popularity and early criticism

Homeopathy achieved its greatest popularity in the 19th century. It was introduced to the United States in 1825 by Hans Birch Gram, a student of Hahnemann.
The first homeopathic school in the United States opened in 1835 and the
American Institute of Homeopathy was established in 1844. Throughout the 19th century, dozens of homeopathic institutions appeared in Europe and the United States,
and by 1900, there were 22 homeopathic colleges and 15,000 practitioners in the United States.
Because medical practice of the time relied on treatments which were often ineffective and harmful, patients of homeopaths often had better outcomes than those being treated by medical practitioners.
Though ineffective, homeopathic preparations are rarely detrimental, thus users are less likely to be harmed by the treatment that is supposed to be helping them.
The relative success of homeopathy in the 19th century may have led to the abandonment of the ineffective and harmful treatments of
bloodletting
Bloodletting (or blood-letting) was the deliberate withdrawal of blood from a patient to prevent or cure illness and disease. Bloodletting, whether by a physician or by leeches, was based on an ancient system of medicine in which blood and othe ...
and purging and begun the move towards more effective,
science-based medicine.
[
] One reason for the growing popularity of homeopathy was its apparent success in treating people suffering from infectious disease epidemics. During 19th-century epidemics of diseases such as
cholera
Cholera () is an infection of the small intestine by some Strain (biology), strains of the Bacteria, bacterium ''Vibrio cholerae''. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea last ...
, death rates in homeopathic hospitals were often lower than in conventional hospitals, where the treatments used at the time were often harmful and did little or nothing to combat the diseases.
Even during its rise in popularity, homeopathy was criticized by scientists and physicians.
Sir John Forbes, physician to
Queen Victoria
Victoria (Alexandrina Victoria; 24 May 1819 – 22 January 1901) was Queen of the United Kingdom of Great Britain and Ireland from 20 June 1837 until Death and state funeral of Queen Victoria, her death in January 1901. Her reign of 63 year ...
, said in 1843 that the extremely small doses of homeopathy were regularly derided as useless and considered it "an outrage to human reason".
[
] James Young Simpson said in 1853 of the highly diluted drugs: "No poison, however strong or powerful, the billionth or decillionth of which would in the least degree affect a man or harm a fly." Nineteenth-century American physician and author
Oliver Wendell Holmes was also a vocal critic of homeopathy and published an essay entitled ''
Homœopathy and Its Kindred Delusions'' (1842).
The members of the French Homeopathic Society observed in 1867 that some leading homeopaths of Europe not only were abandoning the practice of administering infinitesimal doses but were also no longer defending it. The last school in the United States exclusively teaching homeopathy closed in 1920.
Revival in the 20th century
According to academics and
Edzard Ernst
Edzard Ernst (born 30 January 1948) is a retired British-German academic physician and researcher specializing in the study of complementary and alternative medicine. He was Professor of Complementary Medicine at the University of Exeter, the wo ...
, the
Nazi
Nazism (), formally named National Socialism (NS; , ), is the far-right politics, far-right Totalitarianism, totalitarian socio-political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in Germany. During H ...
regime in Germany was fond of homeopathy, and spent large sums of money on researching its mechanisms, but without gaining a positive result. Unschuld also states that homeopathy never subsequently took root in the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
, but remained more deeply established in European thinking.
In the United States, the ''
Food, Drug, and Cosmetic Act'' of 1938 (sponsored by
Royal Copeland, a
Senator
A senate is a deliberative assembly, often the upper house or Legislative chamber, chamber of a bicameral legislature. The name comes from the Ancient Rome, ancient Roman Senate (Latin: ''Senatus''), so-called as an assembly of the senior ...
from
New York and homeopathic physician) recognized homeopathic preparations as drugs. In the 1950s, there were only 75 solely homeopathic practitioners in the U.S. By the mid to late 1970s, homeopathy made a significant comeback and the sales of some homeopathic companies increased tenfold.
[
]
Some homeopaths credit the revival to Greek homeopath
George Vithoulkas
George Vithoulkas (; born 25 July 1932, in Athens)
is a Greek teacher and practitioner of homeopathy.
He studied homeopathy in South Africa and received a diploma in homeopathy from the Indian Institute of Homeopathy in 1966. Upon receiving hi ...
, who conducted a "great deal of research to update the scenarios and refine the theories and practice of homeopathy" in the 1970s,
but Ernst and
Simon Singh consider it to be linked to the rise of the
New Age movement
New Age is a range of spiritual or religious practices and beliefs that rapidly grew in Western society during the early 1970s. Its highly eclectic and unsystematic structure makes a precise definition difficult. Although many scholars consid ...
.
Bruce Hood has argued that the increased popularity of homeopathy in recent times may be due to the comparatively long consultations practitioners are willing to give their patients, and to a
preference for "natural" products, which people think are the basis of homeopathic preparations.
Towards the end of the century opposition to homeopathy began to increase again; with
William T. Jarvis, the President of the
National Council Against Health Fraud
The National Council Against Health Fraud (NCAHF) was a not-for-profit, US-based organization, that described itself as a "private nonprofit, voluntary health agency that focuses upon health misinformation, fraud, and quackery as public health pr ...
, saying that "Homeopathy is a fraud perpetrated on the public with the government's blessing, thanks to the abuse of political power of Sen. Royal S. Copeland."
21st century: renewed criticism
Since the beginning of the 21st century, a series of
meta-analyses
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...
have further shown that the therapeutic claims of homeopathy lack scientific justification.
This had led to a decrease or suspension of funding by many governments. In a 2010 report, the
Science and Technology Committee of the United Kingdom House of Commons recommended that homeopathy should no longer receive
National Health Service
The National Health Service (NHS) is the term for the publicly funded health care, publicly funded healthcare systems of the United Kingdom: the National Health Service (England), NHS Scotland, NHS Wales, and Health and Social Care (Northern ...
(NHS) funding due its lack of scientific credibility;
NHS funding for homeopathy ceased in 2017.
They also asked the
Department of Health in the UK to add homeopathic remedies to the list of forbidden prescription items.
In 2015, the
National Health and Medical Research Council
The National Health and Medical Research Council (NHMRC) is the main statutory authority of the Australian Government responsible for medical research. It was the eighth largest research funding body in the world in 2016, and NHMRC-funded res ...
of Australia found that "there are no health conditions for which there is reliable evidence that homeopathy is effective". The federal government only ended up accepting three of the 45 recommendations made by the 2018 review of Pharmacy Remuneration and Regulation. The same year the US
Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respo ...
(FDA) held a hearing requesting public comment on the regulation of homeopathic drugs.
In 2017 the FDA announced it would strengthen regulation of homeopathic products.
The American non-profit
Center for Inquiry
The Center for Inquiry (CFI) is a U.S. nonprofit organization that works to mitigate belief in pseudoscience and the paranormal and to fight the influence of religion in government.
History
The Center for Inquiry was established in 1991 by ...
(CFI) filed a lawsuit in 2018 against the
CVS pharmacy for consumer fraud over its sale of homeopathic medicines.
It claimed that CVS was selling homeopathic products on an easier-to-obtain basis than standard medication. In 2019, CFI brought a similar lawsuit against
Walmart
Walmart Inc. (; formerly Wal-Mart Stores, Inc.) is an American multinational retail corporation that operates a chain of hypermarkets (also called supercenters), discount department stores, and grocery stores in the United States and 23 other ...
for "committing wide-scale consumer fraud and endangering the health of its customers through its sale and marketing of homeopathic medicines". They also conducted a survey in which they found consumers felt ripped off when informed of the lack of evidence for the efficacy of homeopathic remedies, such as those sold by Walmart and CVS.
In 2021, the French healthcare minister phased out social security reimbursements for homeopathic drugs.
France has long had a stronger belief in the virtues of homeopathic drugs than many other countries and the world's biggest manufacturer of alternative medicine drugs,
Boiron, is located in that country. Spain has also announced moves to ban homeopathy and other pseudotherapies.
In 2016, the
University of Barcelona
The University of Barcelona (official name in ; UB), formerly also known as Central University of Barcelona (), is a public research university located in the city of Barcelona, Catalonia, Spain. It was established in 1450. With 76,000 students, ...
cancelled its master's degree in Homeopathy citing "lack of scientific basis", after advice from the Spanish Ministry of Health. Shortly afterwards the
University of Valencia
The University of Valencia ( ), shortened to UV, is a public research university in Valencia, Spain. It is one of the oldest universities in Spain, and the oldest in the Valencian Community. It is regarded as one of Spain's leading academic i ...
announced the elimination of its Masters in Homeopathy.
Preparations and treatment

Homeopathic preparations are referred to as "homeopathic remedies".
Practitioners rely on two types of reference when prescribing: ''
Materia medica'' and repertories. A homeopathic ''materia medica'' is a collection of "drug pictures", organized alphabetically. A homeopathic repertory is a quick reference version of the ''materia medica'' that indexes the symptoms and then the associated remedies for each. In both cases different compilers may dispute particular inclusions in the references. The first symptomatic homeopathic ''materia medica'' was arranged by Hahnemann. The first homeopathic repertory was Georg Jahr's ''Symptomenkodex'', published in German in 1835, and translated into English as the ''Repertory to the more Characteristic Symptoms of Materia Medica'' in 1838. This version was less focused on disease categories and was the forerunner to later works by
James Tyler Kent
James Tyler Kent (1849–1916) was an American physician best remembered as a forefather of modern homeopathy. In 1897 Kent published a massive guidebook on human physical and mental disease symptoms and their associated pseudoscientific home ...
.
There are over 118 repertories published in English, with Kent's being one of the most used.
Consultation
Homeopaths generally begin with a consultation, which can be a 10–15 minute appointment or last for over an hour, where the patient describes their
medical history
The medical history, case history, or anamnesis (from Greek: ἀνά, ''aná'', "open", and μνήσις, ''mnesis'', "memory") of a patient is a set of information the physicians collect over medical interviews. It involves the patient, and ev ...
. The patient describes the "modalities", or if their symptoms change depending on the weather and other external factors.
The practitioner also solicits information on mood, likes and dislikes, physical, mental and emotional states, life circumstances, and any physical or emotional illnesses.
[
] This information (also called the "symptom picture") is matched to the "drug picture" in the ''materia medica'' or repertory and used to determine the appropriate homeopathic remedies. In classical homeopathy, the practitioner attempts to match a single preparation to the totality of symptoms (the ''simlilum''), while "clinical homeopathy" involves combinations of preparations based on the illness's symptoms.
Preparation

Homeopathy uses animal, plant, mineral, and synthetic substances in its preparations, generally referring to them using
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
names.
Examples include ''
arsenicum album'' (arsenic oxide), ''natrum muriaticum'' (
sodium chloride
Sodium chloride , commonly known as Salt#Edible salt, edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is transparent or translucent, brittle, hygroscopic, and occurs a ...
or table salt), ''
Lachesis muta
''Lachesis muta'', also known as the Southern American bushmaster or Atlantic bushmaster, is a pit viper species found in South America, as well as the island of Trinidad in the Caribbean. Two subspecies are currently recognized, including the no ...
'' (the venom of the
bushmaster snake), ''
opium
Opium (also known as poppy tears, or Lachryma papaveris) is the dried latex obtained from the seed Capsule (fruit), capsules of the opium poppy ''Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid mor ...
'', and ''thyroidinum'' (
thyroid hormone). Homeopaths say this is to ensure accuracy. In the USA the common name must be displayed, although the Latin one can also be present.
Homeopathic pills are made from an inert substance (often sugars, typically lactose), upon which a drop of liquid homeopathic preparation is placed and allowed to evaporate.
Isopathy is a therapy derived from homeopathy in which the preparations come from diseased or pathological products such as fecal, urinary and respiratory discharges, blood, and tissue.
They are called nosodes (from the Greek ''nosos'', disease) with preparations made from "healthy" specimens being termed "sarcodes". Many so-called "homeopathic vaccines" are a form of isopathy. Tautopathy is a form of isopathy where the preparations are composed of drugs or
vaccine
A vaccine is a biological Dosage form, preparation that provides active acquired immunity to a particular infectious disease, infectious or cancer, malignant disease. The safety and effectiveness of vaccines has been widely studied and verifi ...
s that a person has consumed in the past, in the belief that this can reverse the supposed lingering damage caused by the initial use. There is no convincing scientific evidence for isopathy as an effective method of treatment.
Some modern homeopaths use preparations they call "imponderables" because they do not originate from a substance but some other phenomenon presumed to have been "captured" by alcohol or
lactose
Lactose is a disaccharide composed of galactose and glucose and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from (Genitive case, gen. ), the Latin word for milk, plus the suffix ''-o ...
. Examples include
X-ray
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
s and
sunlight
Sunlight is the portion of the electromagnetic radiation which is emitted by the Sun (i.e. solar radiation) and received by the Earth, in particular the visible spectrum, visible light perceptible to the human eye as well as invisible infrare ...
. Another derivative is
electrohomeopathy, where an electric bio-energy of therapeutic value is supposedly extracted from plants. Popular in the late nineteenth century, electrohomeopathy is extremely pseudo-scientific. In 2012, the Allahabad High Court in Uttar Pradesh, India, handed down a decree stating that electrohomeopathy was quackery and no longer recognized it as a system of medicine.
Other minority practices include paper preparations, in which the terms for substances and dilutions are written on pieces of paper and either pinned to the patients' clothing, put in their pockets, or placed under glasses of water that are then given to the patients.
Radionics
Radionics—also called electromagnetic therapy (EMT) and the Abrams method—is a form of alternative medicine that claims that disease can be diagnosed and treated by applying electromagnetic radiation (EMR), such as radio waves, to the bod ...
, the use of
electromagnetic radiation
In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...
such as
radio wave
Radio waves (formerly called Hertzian waves) are a type of electromagnetic radiation with the lowest frequencies and the longest wavelengths in the electromagnetic spectrum, typically with frequencies below 300 gigahertz (GHz) and wavelengths g ...
s, can also be used to manufacture preparations. Such practices have been strongly criticized by classical homeopaths as unfounded, speculative, and verging upon magic and superstition.
[
] Flower preparations are 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
Edward Bach.
Dilutions
Hahnemann claimed that undiluted doses caused reactions, sometimes dangerous ones, and thus that preparations be given at the lowest possible dose.
[
] A solution that is more dilute is described as having a higher "potency", and thus are claimed to be stronger and deeper-acting. The general method of dilution is
serial dilution, where solvent is added to part of the previous mixture, but the "Korsakovian" method may also be used. In the Korsakovian method, the vessel in which the preparations are manufactured is emptied, refilled with solvent, with the volume of fluid adhering to the walls of the vessel deemed sufficient for the new batch.
The Korsakovian method is sometimes referred to as K on the label of a homeopathic preparation. Another method is Fluxion, which dilutes the substance by continuously passing water through the vial. Insoluble solids, such as
granite
Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly coo ...
,
diamond
Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of e ...
, and
platinum
Platinum is a chemical element; it has Symbol (chemistry), symbol Pt and atomic number 78. It is a density, dense, malleable, ductility, ductile, highly unreactive, precious metal, precious, silverish-white transition metal. Its name origina ...
, are diluted by grinding them with lactose ("
trituration").
Three main
logarithmic dilution scales are in regular use in homeopathy. Hahnemann created the "centesimal" or "C scale", diluting a substance by a factor of 100 at each stage. There is also a decimal dilution scale (notated as "X" or "D") in which the preparation is diluted by a factor of 10 at each stage. The centesimal scale was favoured by Hahnemann for most of his life, although in his last ten years Hahnemann developed a quintamillesimal (Q) scale which diluted the drug 1 part in 50,000. A 2C dilution works out to one part of the original substance in 10,000 parts of the solution. In standard chemistry, this produces a substance with a concentration of 0.01% (
volume-volume percentage). A 6C dilution ends up with the original substance diluted by a factor of 100
−6 (one part in one trillion). The end product is usually so diluted as to be indistinguishable from the diluent (pure water, sugar or alcohol).
[
] The greatest dilution reasonably likely to contain at least one molecule of the original substance is approximately 12C.
Hahnemann advocated dilutions of 1 part to 10
60 or 30C.
[
] Hahnemann regularly used dilutions of up to 30C but opined that "there must be a limit to the matter".
To counter the reduced potency at high dilutions he formed the view that vigorous shaking by striking on an elastic surface – a process termed ''succussion'' – was necessary.
Homeopaths are unable to agree on the number and force of strikes needed, and there is no way that the claimed results of succussion can be tested.
Critics of homeopathy commonly emphasize the dilutions involved in homeopathy, using analogies.
[For further discussion of homeopathic dilutions and the mathematics involved, see Homeopathic dilutions.] One mathematically correct example is that a 12C solution is equivalent to "a pinch of salt in both the North and South Atlantic Oceans".
[
][
] One-third of a
drop of some original substance diluted into all the water on Earth would produce a preparation with a concentration of about 13C.
Robert L. Park points out that a 200C dilution of duck liver, marketed under the name
Oscillococcinum, would require 10
320 universes worth of molecules to contain just one original molecule in the final substance. The high dilutions characteristically used are often considered to be the most controversial and implausible aspect of homeopathy.
Provings
Homeopaths claim that they can determine the properties of their preparations by following a method which they call "proving". As performed by Hahnemann, provings involved administering various preparations to healthy volunteers. The volunteers were then observed, often for months at a time. They were 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. At first Hahnemann used undiluted doses for provings, but he later advocated provings with preparations at a 30C dilution,
and most modern provings are carried out using ultra-dilute preparations.
Provings are claimed to have been important in the development of the
clinical trial
Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...
, due to their early use of simple control groups, systematic and quantitative procedures, and some of the first application of
statistics
Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...
in medicine. The lengthy records of
self-experimentation by homeopaths have occasionally proven useful in the development of modern drugs: For example, evidence that
nitroglycerin
Nitroglycerin (NG) (alternative spelling nitroglycerine), also known as trinitroglycerol (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless or pale yellow, oily, explosive liquid most commonly produced by ...
might be useful as a treatment for
angina
Angina, also known as angina pectoris, is chest pain or pressure, usually caused by insufficient blood flow to the heart muscle (myocardium). It is most commonly a symptom of coronary artery disease.
Angina is typically the result of parti ...
was discovered by looking through homeopathic provings, though homeopaths themselves never used it for that purpose at that time.
[
] The first recorded provings were published by Hahnemann in his 1796 ''Essay on a New Principle''. His ''Fragmenta de Viribus'' (1805) contained the results of 27 provings, and his 1810 ''Materia Medica Pura'' contained 65. For James Tyler Kent's 1905 ''Lectures on Homoeopathic Materia Medica'', 217 preparations 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.
As early as 1842, Oliver Holmes had noted that provings were impossibly vague, and the purported effect was not repeatable among different subjects.
Evidence and efficacy
Outside of the
alternative medicine
Alternative medicine refers to practices that aim to achieve the healing effects of conventional medicine, but that typically lack biological plausibility, testability, repeatability, or supporting evidence of effectiveness. Such practices are ...
community, scientists have long considered homeopathy a sham
or a
pseudoscience
Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable cl ...
,
and the medical community regards it as
quackery
Quackery, often synonymous with health fraud, is the promotion of fraudulent or Ignorance, ignorant medicine, medical practices. A quack is a "fraudulent or ignorant pretender to medical skill" or "a person who pretends, professionally or public ...
.
There is an overall absence of sound
statistical evidence of therapeutic efficacy, which is consistent with the lack of any
biologically plausible pharmacological
agent or mechanism.
Proponents argue that homeopathic medicines must work by some, as yet undefined, biophysical mechanism.
No homeopathic preparation has been shown to be different from
placebo
A placebo ( ) can be roughly defined as a sham medical treatment. Common placebos include inert tablets (like sugar pills), inert injections (like saline), sham surgery, and other procedures.
Placebos are used in randomized clinical trials ...
.
Lack of scientific evidence
The lack of convincing scientific evidence supporting its efficacy
and its use of preparations without active ingredients have led to characterizations of homeopathy as pseudoscience and quackery,
or, in the words of a 1998 medical review, "placebo therapy at best and quackery at worst".
The
Russian Academy of Sciences
The Russian Academy of Sciences (RAS; ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across the Russian Federation; and additional scientific and social units such ...
considers homeopathy a "dangerous 'pseudoscience' that does not work", and "urges people to treat homeopathy 'on a par with magic.
The Chief Medical Officer for England,
Dame Sally Davies, has stated that homeopathic preparations are "rubbish" and do not serve as anything more than placebos. In 2013,
Mark Walport
Sir Mark Jeremy Walport (born 25 January 1953) is an English medical scientist and was the Government Chief Scientific Adviser in the United Kingdom from 2013 to 2017 and Chief Executive of UK Research and Innovation (UKRI) from 2017 to 2020. I ...
, the UK
Government Chief Scientific Adviser
The UK Government Chief Scientific Adviser (GCSA) is the personal adviser on science and technology-related activities and policies to the Prime Minister and the Cabinet. They are also the head of the Government Office for Science.
Many indiv ...
and head of the
Government Office for Science said "homeopathy is nonsense, it is non-science."
His predecessor,
John Beddington, also said that homeopathy "has no underpinning of scientific basis" and is being "fundamentally ignored" by the Government.
Jack Killen, acting deputy director of the
National Center for Complementary and Alternative Medicine, says homeopathy "goes beyond current understanding of chemistry and physics". He adds: "There is, to my knowledge, no condition for which homeopathy has been proven to be an effective treatment."
Ben Goldacre says that homeopaths who misrepresent scientific evidence to a
scientifically illiterate public, have "... walled themselves off from academic medicine, and critique has been all too often met with avoidance rather than argument".
Homeopaths often prefer to ignore
meta-analyses
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...
in favour of
cherry picked positive results, such as by promoting a particular
observational study
In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample (statistics), sample to a statistical population, population where the dependent and independent variables, independ ...
(one which Goldacre describes as "little more than a customer-satisfaction survey") as if it were more informative than a series of randomized controlled trials.
In an article entitled "Should We Maintain an Open Mind about Homeopathy?"
published in the ''
American Journal of Medicine'',
Michael Baum and
Edzard Ernst
Edzard Ernst (born 30 January 1948) is a retired British-German academic physician and researcher specializing in the study of complementary and alternative medicine. He was Professor of Complementary Medicine at the University of Exeter, the wo ...
writing to other physicianswrote that "Homeopathy is among the worst examples of faith-based medicine... These axioms
f homeopathy
F, or f, is the sixth Letter (alphabet), letter of the Latin alphabet and many modern alphabets influenced by it, including the English alphabet, modern English alphabet and the alphabets of all other modern western European languages. Its n ...
are not only out of line with scientific facts but also directly opposed to them. If homeopathy is correct, much of physics, chemistry, and pharmacology must be incorrect...".
Plausibility of dilutions

The exceedingly low concentration of homeopathic preparations, which often lack even a single
molecule
A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...
of the diluted substance,
has been the basis of questions about the effects of the preparations since the 19th century.
The laws of chemistry give this dilution limit, which is related to the
Avogadro number
The Avogadro constant, commonly denoted or , is an SI defining constant with an exact value of when expressed in reciprocal moles.
It defines the ratio of the number of constituent particles to the amount of substance in a sample, where th ...
, as being roughly equal to 12C homeopathic dilutions (1 part in 10
24).
James Randi and the
10:23 campaign groups have highlighted the lack of
active ingredient
An active ingredient is any ingredient that provides biologically active or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or any function of the body of humans or animals.
...
s by taking large 'overdoses'.
[Sam Jones]
"Homeopathy protesters to take 'mass overdose' outside Boots"
''The Guardian
''The Guardian'' is a British daily newspaper. It was founded in Manchester in 1821 as ''The Manchester Guardian'' and changed its name in 1959, followed by a move to London. Along with its sister paper, ''The Guardian Weekly'', ''The Guardi ...
'', January 29, 2010 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".
Modern advocates of homeopathy have proposed a concept of "
water memory", according to which water "remembers" the substances mixed in it, and transmits the effect of those substances when consumed. This concept is inconsistent with the current understanding of matter, and water memory has never been demonstrated to have any detectable effect, biological or otherwise.
Existence of a
pharmacological effect in the absence of any true active ingredient is inconsistent with the
law of mass action
In chemistry, the law of mass action is the proposition that the rate of a chemical reaction is directly proportional to the product of the activities or concentrations of the reactants. It explains and predicts behaviors of solutions in dy ...
and the observed
dose-response relationships characteristic of therapeutic drugs.
Homeopaths contend that their methods produce a therapeutically active preparation, selectively including only the intended substance, though in reality any water will have been in contact with millions of different substances throughout its history, and homeopaths cannot account for the selected homeopathic substance being isolated as a special case in their process.
Practitioners also hold that higher dilutions produce stronger medicinal effects. This idea is also inconsistent with observed dose-response relationships, where effects are dependent on the concentration of the active ingredient in the body.
Some contend that the phenomenon of
hormesis may support the idea of dilution increasing potency, but the dose-response relationship outside the zone of hormesis declines with dilution as normal, and nonlinear pharmacological effects do not provide any credible support for homeopathy.
Efficacy
No individual homeopathic preparation has been unambiguously shown by research to be different from placebo.
The
methodological
In its most common sense, methodology is the study of research methods. However, the term can also refer to the methods themselves or to the philosophical discussion of associated background assumptions. A method is a structured procedure for bri ...
quality of the early primary research was low, with problems such as weaknesses in
study design
Clinical study design is the formulation of clinical trials and other experiments, as well as observational studies, in medical research involving human beings and involving clinical aspects, including epidemiology . It is the design of experim ...
and reporting, small
sample size
Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. The sample size is an important feature of any empirical study in which the goal is to make inferences abo ...
, and
selection bias
Selection bias is the bias introduced by the selection of individuals, groups, or data for analysis in such a way that proper randomization is not achieved, thereby failing to ensure that the sample obtained is representative of the population inte ...
. Since better quality trials have become available, the evidence for efficacy of homeopathy preparations has diminished; the highest-quality trials indicate that the preparations themselves exert no intrinsic effect.
A review conducted in 2010 of all the pertinent studies of "best evidence" produced by the
Cochrane Collaboration
Cochrane is a British international charitable organisation formed to synthesize medical research findings to facilitate evidence-based choices about health interventions involving health professionals, patients and policy makers. It includes ...
concluded that this evidence "fails to demonstrate that homeopathic medicines have effects beyond placebo."
In 2009, the United Kingdom's
House of Commons
The House of Commons is the name for the elected lower house of the Bicameralism, bicameral parliaments of the United Kingdom and Canada. In both of these countries, the Commons holds much more legislative power than the nominally upper house of ...
Science and Technology Committee concluded that there was no compelling evidence of effect other than placebo.
[UK Parliamentary Committee Science and Technology Committee]
"Evidence Check 2: Homeopathy"
/ref> The Australian National Health and Medical Research Council
The National Health and Medical Research Council (NHMRC) is the main statutory authority of the Australian Government responsible for medical research. It was the eighth largest research funding body in the world in 2016, and NHMRC-funded res ...
completed a comprehensive review of the effectiveness of homeopathic preparations in 2015, in which it concluded that "there were no health conditions for which there was reliable evidence that homeopathy was effective." The European Academies' Science Advisory Council (EASAC) published its official analysis in 2017 finding a lack of evidence that homeopathic products are effective, and raising concerns about quality control. In contrast a 2011 book was published, purportedly financed by the Swiss government, that concluded that homeopathy was effective and cost efficient. Although hailed by proponents as proof that homeopathy works, it was found to be scientifically, logically and ethically flawed, with most authors having a conflict of interest
A conflict of interest (COI) is a situation in which a person or organization is involved in multiple wikt:interest#Noun, interests, financial or otherwise, and serving one interest could involve working against another. Typically, this relates t ...
. The Swiss Federal Office of Public Health later released a statement saying the book was published without the consent of the Swiss government.
Meta-analyses
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...
, essential tools to summarize evidence of therapeutic efficacy, and systematic review
A systematic review is a scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from published studies on ...
s have found that the methodological quality in the majority of randomized trials in homeopathy have shortcomings and that such trials were generally of lower quality than trials of conventional medicine. A major issue has been publication bias
In published academic research, publication bias occurs when the outcome of an experiment or research study biases the decision to publish or otherwise distribute it. Publishing only results that show a Statistical significance, significant find ...
, where positive results are more likely to be published in journals. This has been particularly marked in alternative medicine journals, where few of the published articles (just 5% during the year 2000) tend to report null results. A systematic review of the available systematic reviews confirmed in 2002 that higher-quality trials tended to have less positive results, and found no convincing evidence that any homeopathic preparation exerts clinical effects different from placebo. The same conclusion was also reached in 2005 in a meta-analysis published in ''The Lancet''. A 2017 systematic review and meta-analysis found that the most reliable evidence did not support the effectiveness of non-individualized homeopathy.
Health organizations, including the UK's National Health Service
The National Health Service (NHS) is the term for the publicly funded health care, publicly funded healthcare systems of the United Kingdom: the National Health Service (England), NHS Scotland, NHS Wales, and Health and Social Care (Northern ...
, the American Medical Association
The American Medical Association (AMA) is an American professional association and lobbying group of physicians and medical students. This medical association was founded in 1847 and is headquartered in Chicago, Illinois. Membership was 271,660 ...
, the FASEB, and the National Health and Medical Research Council
The National Health and Medical Research Council (NHMRC) is the main statutory authority of the Australian Government responsible for medical research. It was the eighth largest research funding body in the world in 2016, and NHMRC-funded res ...
of Australia, have issued statements saying that there is no good-quality evidence that homeopathy is effective as a treatment for any health condition. In 2009, World Health Organization
The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...
official Mario Raviglione criticized the use of homeopathy to treat tuberculosis
Tuberculosis (TB), also known colloquially as the "white death", or historically as consumption, is a contagious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can al ...
; similarly, another WHO spokesperson argued there was no evidence homeopathy would be an effective treatment for diarrhoea
Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...
. They warned against the use of homeopathy for serious conditions such as depression, HIV and malaria
Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...
. The American College of Medical Toxicology and the American Academy of Clinical Toxicology recommend that no one use homeopathic treatment for disease or as a preventive health measure.[, which cites ] These organizations report that no evidence exists that homeopathic treatment is effective, but that there is evidence that using these treatments produces harm and can bring indirect health risks by delaying conventional treatment.
Purported effects in other biological systems
While some articles have suggested that homeopathic solutions of high dilution can have statistically significant effects on organic processes including the growth of grain
A grain is a small, hard, dry fruit (caryopsis) – with or without an attached husk, hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and ...
and enzyme reactions, such evidence is disputed since attempts to replicate them have failed. In 2001 and 2004, Madeleine Ennis published a number of studies that reported that homeopathic dilutions of histamine
Histamine is an organic nitrogenous compound involved in local immune responses communication, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Discovered in 19 ...
exerted an effect on the activity of basophils. In response to the first of these studies, ''Horizon
The horizon is the apparent curve that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This curve divides all viewing directions based on whethe ...
'' aired a programme in which British scientists attempted to replicate Ennis' results; they were unable to do so. A 2007 systematic review of high-dilution experiments found that none of the experiments with positive results could be reproduced by all investigators.
In 1988, French immunologist Jacques Benveniste published a paper in the journal ''Nature
Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...
'' while working at INSERM. The paper purported to have discovered that basophils released histamine when exposed to a homeopathic dilution of anti-immunoglobulin E antibody. Skeptical of the findings, ''Nature'' assembled an independent investigative team to determine the accuracy of the research. After investigation the team found that the experiments were "statistically ill-controlled", "interpretation has been clouded by the exclusion of measurements in conflict with the claim", and concluded, "We believe that experimental data have been uncritically assessed and their imperfections inadequately reported."[
][
]
Ethics and safety
The provision of homeopathic preparations has been described as unethical. Michael Baum, professor emeritus of surgery and visiting professor of medical humanities at University College London
University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...
(UCL), has described homeopathy as a "cruel deception". Edzard Ernst
Edzard Ernst (born 30 January 1948) is a retired British-German academic physician and researcher specializing in the study of complementary and alternative medicine. He was Professor of Complementary Medicine at the University of Exeter, the wo ...
, the first professor of complementary medicine in the United Kingdom and a former homeopathic practitioner,[Memorandum submitted by Edzard Ernst HO 16](_blank)
to the House of Lords
The House of Lords is the upper house of the Parliament of the United Kingdom. Like the lower house, the House of Commons of the United Kingdom, House of Commons, it meets in the Palace of Westminster in London, England. One of the oldest ext ...
has expressed his concerns about pharmacist
A pharmacist, also known as a chemist in English in the Commonwealth of Nations, Commonwealth English, is a healthcare professional who is knowledgeable about preparation, mechanism of action, clinical usage and legislation of medications in ...
s who violate their ethical code by failing to provide customers with "necessary and relevant information" about the true nature of the homeopathic products they advertise and sell. In 2013 the UK Advertising Standards Authority concluded that the Society of Homeopaths
The Society of Homeopaths (SoH) is a British private limited company formed in 1978 by "a small group of homeopaths who were keen to work together for the development of the profession and to ensure high standards in the practice of homeopathy" and ...
were targeting vulnerable ill people and discouraging the use of essential medical treatment while making misleading claims of efficacy for homeopathic products. In 2015 the Federal Court of Australia
The Federal Court of Australia is an Australian superior court which has jurisdiction to deal with most civil disputes governed by federal law (with the exception of family law matters), along with some summary (less serious) and indictable (mo ...
imposed penalties on a homeopathic company for making false or misleading statements about the efficacy of the whooping cough vaccine and recommending homeopathic remedies as an alternative.
A 2000 review by homeopaths reported that homeopathic preparations are "unlikely to provoke severe adverse reactions". In 2012, a systematic review evaluating evidence of homeopathy's possible adverse effect
An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term compli ...
s concluded that "homeopathy has the potential to harm patients and consumers in both direct and indirect ways". A 2016 systematic review and meta-analysis found that, in homeopathic clinical trials, adverse effects were reported among the patients who received homeopathy about as often as they were reported among patients who received placebo or conventional medicine.
Some homeopathic preparations involve poisons such as Belladonna, arsenic
Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is not ...
, and poison ivy
Poison ivy is a type of allergenic plant in the genus '' Toxicodendron'' native to Asia and North America. Formerly considered a single species, '' Toxicodendron radicans'', poison ivies are now generally treated as a complex of three separate s ...
. In rare cases, the original ingredients are present at detectable levels. This may be due to improper preparation or intentional low dilution. Serious adverse effects such as seizures and death have been reported or associated with some homeopathic preparations. Instances of arsenic poisoning have occurred. In 2009, the FDA advised consumers to stop using three discontinued cold remedy Zicam products because it could cause permanent damage to users' sense of smell. In 2016 the FDA issued a safety alert to consumers warning against the use of homeopathic teething gels and tablets following reports of adverse events after their use. A previous FDA investigation had found that these products were improperly diluted and contained "unsafe levels of belladonna" and that the reports of serious adverse events in children using this product were "consistent with belladonna toxicity".
Patients who choose to use homeopathy rather than evidence-based medicine
Evidence-based medicine (EBM) is "the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. It means integrating individual clinical expertise with the best available exte ...
risk missing timely diagnosis and effective treatment, thereby worsening the outcomes of serious conditions such as cancer. The Russian Commission on Pseudoscience
The Commission on Pseudoscience () is a Russian scientific organization under the , created on the initiative of Vitaly Ginzburg in 1998. Until 2018, the organization was a member of the Commission on Pseudoscience and Falsification of Scientific ...
has said homeopathy is not safe because "patients spend significant amounts of money, buying medicines that do not work and disregard already known effective treatment." Critics have cited cases of patients failing to receive proper treatment for diseases that could have been easily managed with conventional medicine and who have died as a result.[Case of Baby Gloria, who died in 2002:
*
*] They have also condemned the "marketing practice" of criticizing and downplaying the effectiveness of medicine. Homeopaths claim that use of conventional medicines will "push the disease deeper" and cause more serious conditions, a process referred to as "suppression". In 1978, Anthony Campbell, a consultant physician at the Royal London Homeopathic Hospital, criticized statements by George Vithoulkas
George Vithoulkas (; born 25 July 1932, in Athens)
is a Greek teacher and practitioner of homeopathy.
He studied homeopathy in South Africa and received a diploma in homeopathy from the Indian Institute of Homeopathy in 1966. Upon receiving hi ...
claiming that syphilis
Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms depend on the stage it presents: primary, secondary, latent syphilis, latent or tertiary. The prim ...
, when treated with antibiotics, would develop into secondary and tertiary syphilis with involvement of the central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...
. Vithoulkas' claims echo the idea that treating a disease with external medication used to treat the symptoms would only drive it deeper into the body and conflict with scientific studies, which indicate that penicillin
Penicillins (P, PCN or PEN) are a group of beta-lactam antibiotic, β-lactam antibiotics originally obtained from ''Penicillium'' Mold (fungus), moulds, principally ''Penicillium chrysogenum, P. chrysogenum'' and ''Penicillium rubens, P. ru ...
treatment produces a complete cure of syphilis in more than 90% of cases.
The use of homeopathy as a preventive for serious infectious diseases, called homeoprophylaxis, is especially controversial. Some homeopaths (particularly those who are non-physicians) advise their patients against immunization
Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the antigen, immunogen). When this system is exposed to molecules that are foreign to the body, called ' ...
. Others have suggested that vaccines be replaced with homeopathic "nosodes". While Hahnemann was opposed to such preparations, modern homeopaths often use them although there is no evidence to indicate they have any beneficial effects. Promotion of homeopathic alternatives to vaccines has been characterized as dangerous, inappropriate and irresponsible. In December 2014, the Australian homeopathy supplier Homeopathy Plus! was found to have acted deceptively in promoting homeopathic alternatives to vaccines. In 2019, an investigative journalism piece by the ''Telegraph'' revealed that homeopathy practitioners were actively discouraging patients from vaccinating their children. Cases of homeopaths advising against the use of anti-malarial drugs have also been identified, putting visitors to the tropics in severe danger.[
][
]
A 2006 review recommends that pharmacy colleges include a required course where ethical dilemmas inherent in recommending products lacking proven safety and efficacy data be discussed and that students should be taught where unproven systems such as homeopathy depart from evidence-based medicine.
Regulation and prevalence
Homeopathy is fairly common in some countries while being uncommon in others; is highly regulated in some countries and mostly unregulated in others. It is practiced worldwide and professional qualifications and licences are needed in most countries. A 2019 WHO report found that 100 out of 133 Member States surveyed in 2012 acknowledged that their population used homeopathy, with 22 saying the practice was regulated and 13 providing health insurance coverage. In some countries, there are no specific legal regulations concerning the use of homeopathy, while in others, licences or degrees in conventional medicine from accredited universities are required. In 2001 homeopathy had been integrated into the national health care systems of many countries, including India, Mexico, Pakistan, Sri Lanka, and the United Kingdom.
Regulation
Some homeopathic treatment is covered by the public health service of several European countries, including Scotland, and Luxembourg
Luxembourg, officially the Grand Duchy of Luxembourg, is a landlocked country in Western Europe. It is bordered by Belgium to the west and north, Germany to the east, and France on the south. Its capital and most populous city, Luxembour ...
. It used to be covered in France until 2021. In other countries, such as Belgium, homeopathy is not covered. In Austria, the public health service requires scientific proof of effectiveness in order to reimburse medical treatments and homeopathy is listed as not reimbursable, but exceptions can be made; private health insurance policies sometimes include homeopathic treatments. In 2018, Austria's Medical University of Vienna
The Medical University of Vienna (MedUni Wien, German language, German: ''Medizinische Universität Wien'') is a public university located in Vienna, Austria. It is the direct successor to the faculty of medicine at the University of Vienna, foun ...
stopped teaching homeopathy. The Swiss government withdrew coverage of homeopathy and four other complementary treatments in 2005, stating that they did not meet efficacy and cost-effectiveness criteria, but following a referendum in 2009 the five therapies were reinstated for a further 6-year trial period. In Germany, homeopathic treatments are covered by 70 percent of government medical plans, and available in almost every pharmacy. In January 2024, German health minister Karl Lauterbach announced plans to withdraw all statutory health insurance coverage for homeopathic and anthroposophic treatments, citing a lack of scientific evidence for their efficacy.
The English NHS recommended against prescribing homeopathic preparations in 2017. In 2018, prescriptions worth £55,000 were written in defiance of the guidelines, representing less than 0.001% of the total NHS prescribing budget. In 2016 the UK's Committee of Advertising Practice compliance team wrote to homeopaths in the UK to "remind them of the rules that govern what they can and can't say in their marketing materials". The letter told homeopaths to "ensure that they do not make any direct or implied claims that homeopathy can treat medical conditions" and asks them to review their marketing communications "including websites and social media pages" to ensure compliance. Homeopathic services offered at Bristol Homeopathic Hospital in the UK ceased in October 2015.
Member states of the European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
are required to ensure that homeopathic products are registered, although this process does not require any proof of efficacy. In Spain, the Association for the protection of patients from pseudo-scientific therapies is lobbying to get rid of the easy registration procedure for homeopathic remedies. In Bulgaria, Hungary, Latvia, Romania and Slovenia homeopathy, by law, can only be practiced by medical practitioners. However, in Slovenia if doctors practice homeopathy their medical license will be revoked. In Germany, to become a homeopathic physician, one must attend a three-year training program, while France, Austria and Denmark mandate licences to diagnose any illness or dispense of any product whose purpose is to treat any illness. Homeopaths in the UK are under no legal regulations, meaning anyone can call themselves homeopaths and administer homeopathic remedies.
The Indian government
The Government of India (ISO: Bhārata Sarakāra, legally the Union Government or Union of India or the Central Government) is the national authority of the Republic of India, located in South Asia, consisting of 36 states and union territor ...
recognizes homeopathy as one of its national systems of medicine and they are sold with medical claims. It has established the Department of Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy (AYUSH) under the Ministry of Health & Family Welfare. The south Indian state of Kerala
Kerala ( , ) is a States and union territories of India, state on the Malabar Coast of India. It was formed on 1 November 1956, following the passage of the States Reorganisation Act, by combining Malayalam-speaking regions of the erstwhile ...
also has a cabinet-level AYUSH department. The Central Council of Homoeopathy was established in 1973 to monitor higher education in homeopathy, and the National Institute of Homoeopathy in 1975. Principals and standards for homeopathic products are covered by the '' Homoeopathic pharmacopoeia of India''. A minimum of a recognized diploma in homeopathy and registration on a state register or the Central Register of Homoeopathy is required to practice homeopathy in India.
In the United States each state is responsible for the laws and licensing requirements for homeopathy. In 2015, the FDA held a hearing on homeopathic product regulation. At the hearing, representatives from the Center for Inquiry
The Center for Inquiry (CFI) is a U.S. nonprofit organization that works to mitigate belief in pseudoscience and the paranormal and to fight the influence of religion in government.
History
The Center for Inquiry was established in 1991 by ...
and the Committee for Skeptical Inquiry
The Committee for Skeptical Inquiry (CSI), formerly known as the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP), is a program within the U.S. non-profit organization Center for Inquiry (CFI), which seeks to " ...
summarized the harm that is done to the general public from homeopathics and proposed regulatory actions: In 2016 the United States Federal Trade Commission
The Federal Trade Commission (FTC) is an independent agency of the United States government whose principal mission is the enforcement of civil (non-criminal) United States antitrust law, antitrust law and the promotion of consumer protection. It ...
(FTC) issued an "Enforcement Policy Statement Regarding Marketing Claims for Over-the-Counter Homeopathic Drugs" which specified that the FTC will apply the same standard to homeopathic drugs that it applies to other products claiming similar benefits. A related report concluded that claims of homeopathy effectiveness "are not accepted by most modern medical experts and do not constitute competent and reliable scientific evidence that these products have the claimed treatment effects." In 2019, the FDA removed an enforcement policy that permitted unapproved homeopathics to be sold. Currently no homeopathic products are approved by the FDA.
Homeopathic remedies are regulated as natural health products in Canada. Ontario
Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...
became the first province in the country to regulate the practice of homeopathy, a move that was widely criticized by scientists and doctors. Health Canada
Health Canada (HC; )Health Canada is the applied title under the Federal Identity Program; the legal title is Department of Health (). is the Structure of the Canadian federal government#Departments, with subsidiary units, department of the Gove ...
requires all products to have a licence before being sold and applicants have to submit evidence on "the safety, efficacy and quality of a homeopathic medicine". In 2015 the Canadian Broadcasting Corporation
The Canadian Broadcasting Corporation (), branded as CBC/Radio-Canada, is the Canadian Public broadcasting, public broadcaster for both radio and television. It is a Crown corporation that serves as the national public broadcaster, with its E ...
tested the system by applying for and then receiving a government approved licence for a made-up drug aimed at kids.
In Australia, the sale of homeopathic products is regulated by the Therapeutic Goods Administration. In 2015, the National Health and Medical Research Council
The National Health and Medical Research Council (NHMRC) is the main statutory authority of the Australian Government responsible for medical research. It was the eighth largest research funding body in the world in 2016, and NHMRC-funded res ...
of Australia concluded that there is "no reliable evidence that homeopathy is effective and should not be used to treat health conditions that are chronic, serious, or could become serious". They recommended anyone considering using homeopathy should first get advice from a registered health practitioner. A 2017 review into Pharmacy Remuneration and Regulation recommended that products be banned from pharmacies; while noting the concerns the government did not adopt the recommendation. In New Zealand there are no regulations specific to homeopathy and the New Zealand Medical Association does not oppose the use of homeopathy, a stance that has been called unethical by some doctors.
Prevalence
Homeopathy is one of the most commonly used forms of alternative medicines and it has a large worldwide market. The exact size is uncertain, but information available on homeopathic sales suggests it forms a large share of the medical market.
In 1999, about 1000 UK doctors practiced homeopathy, most being general practitioners who prescribe a limited number of remedies. A further 1500 homeopaths with no medical training are also thought to practice. Over ten thousand German and French doctors use homeopathy. In the United States a National Health Interview Survey estimated 5 million adults and 1 million children used homeopathy in 2011. An analysis of this survey concluded that most cases were self-prescribed for colds and musculoskeletal pain. Major retailers like Walmart
Walmart Inc. (; formerly Wal-Mart Stores, Inc.) is an American multinational retail corporation that operates a chain of hypermarkets (also called supercenters), discount department stores, and grocery stores in the United States and 23 other ...
, CVS, and Walgreens sell homeopathic products that are packaged to resemble conventional medicines.
The homeopathic drug market in Germany is worth about 650 million euro with a 2014 survey finding that 60 percent of Germans reported trying homeopathy. A 2009 survey found that only 17 percent of respondents knew how homeopathic medicine was made. France spent more than US$408 million on homeopathic products in 2008. In the United States the homeopathic market is worth about $3 billion-a-year; with 2.9 billion spent in 2007. Australia spent US$7.3 million on homeopathic medicines in 2008.
In India, a 2014 national health survey found that homeopathy was used by about 3% of the population. Homeopathy is used in China, although it arrived a lot later than in many other countries, partly due to the restriction on foreigners that persisted until late in the nineteenth century. Throughout Africa there is a high reliance on traditional medicines, which can be attributed to the cost of modern medicines and the relative prevalence of practitioners. Many African countries do not have any official training facilities.
Veterinary use
Using homeopathy as a treatment for animals is termed "veterinary homeopathy" and dates back to the inception of homeopathy; Hahnemann himself wrote and spoke of the use of homeopathy in animals other than humans. The use of homeopathy in the organic farming
Organic farming, also known as organic agriculture or ecological farming or biological farming,Labelling, article 30 o''Regulation (EU) 2018/848 of the European Parliament and of the Council of 30 May 2024 on organic production and labelling of ...
industry is heavily promoted. Given that homeopathy's effects in humans are due to the placebo effect and the counseling aspects of the consultation, such treatments are even less effective in animals. 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. This means that animals given homeopathic remedies will continue to suffer, resulting in animal welfare
Animal welfare is the quality of life and overall well-being of animals. Formal standards of animal welfare vary between contexts, but are debated mostly by animal welfare groups, legislators, and academics. Animal welfare science uses measures ...
concerns.
Little existing research on the subject is of a high enough scientific standard to provide reliable data on efficacy. A 2016 review of peer-reviewed articles from 1981 to 2014 by scientists from the University of Kassel
The University of Kassel () is a university founded in 1971 located in Kassel, Hessen, in central Germany. As of February 2022 it had about 25,000 students and about 3300 staff, including more than 300 professors.
A special unit (Studienkoll ...
, Germany, concluded that there is not enough evidence to support homeopathy as an effective treatment of infectious diseases in livestock. The UK's Department for Environment, Food and Rural Affairs
The Department for Environment, Food and Rural Affairs (Defra) is a Departments of the Government of the United Kingdom, ministerial department of the government of the United Kingdom. It is responsible for environmental quality, environmenta ...
(Defra) has adopted a robust position against use of "alternative" pet preparations including homeopathy. The British Veterinary Association's position statement on alternative medicines says that it "cannot endorse" homeopathy, and the Australian Veterinary Association includes it on its list of "ineffective therapies".
See also
* Fringe science
Fringe science refers to ideas whose attributes include being highly speculative or relying on premises already Objection (argument), refuted. The chance of ideas rejected by editors and published outside the mainstream being correct is remote. Wh ...
* List of topics characterized as pseudoscience
This is a list of topics that have been characterized as pseudoscience by academics or researchers, either currently or in the past. Detailed discussion of these topics may be found on their main pages. These characterizations were made in the c ...
* Scientific skepticism
Scientific skepticism or rational skepticism (also spelled scepticism), sometimes referred to as skeptical inquiry, is a position in which one questions the veracity of claims lacking scientific evidence. In practice, the term most commonly ref ...
References
External links
Homeopathy
( NHS Choices, UK)
{{Authority control
Pseudoscience
Obsolete medical theories
1796 introductions
Health fraud