What Is Homeopathy? Principles, History, Evidence and Safety
What is homeopathy, and why does it divide opinion so sharply? This article covers where homeopathy came from, what its founder taught, and how remedies are made and labeled. It also sets out what the research shows and how to stay safe if you choose to use it.
This article is for information only and is not medical advice. Talk to a doctor before using any remedy, especially for a diagnosed condition, during pregnancy or for a child.
1796, by German physician Samuel Hahnemann
“Like cures like,” using highly diluted substances
No reliable evidence it works for any health condition
No homeopathic product is FDA-approved
What is homeopathy? A plain definition
Homeopathy is a system of alternative medicine developed in Germany more than 200 years ago. The US National Center for Complementary and Integrative Health (NCCIH) summarizes it in two ideas. A substance that causes symptoms in a healthy person is believed to cure similar symptoms in a sick one. And the more a substance is diluted, the stronger it is believed to act.
Remedies are made from plants, minerals and animal products. They are diluted step by step, often so far that none of the original substance remains. Treatment is individualized, so two people with the same diagnosis may receive different remedies.
One common mix-up is worth clearing up early. Homeopathy is not the same as herbal medicine. A herbal tea or tincture contains measurable plant compounds. A typical homeopathic remedy is diluted far beyond that point. Some low-dilution products, however, do contain active amounts, which matters for safety.
The principles of homeopathy: what the tradition teaches
Hahnemann and his followers built homeopathy on a set of linked ideas. The table shows each one as the tradition presents it, next to the scientific view.
| Principle | What the tradition teaches | What science says |
|---|---|---|
| Law of similars | “Like cures like.” A substance that produces symptoms in the healthy can cure those symptoms in the sick. | No known biological mechanism supports it. |
| Minimum dose | Serial dilution with vigorous shaking, called potentization, makes a remedy stronger, not weaker. | Contradicts basic chemistry. High dilutions usually contain no original molecules. |
| Provings | Healthy volunteers take a substance and record their symptoms. These form the remedy’s picture. | Most provings lack controls and blinding, so findings are unreliable. |
| Totality of symptoms | Treat the whole person: body, mood, sleep, cravings and reactions to weather. | A detailed history is good practice, but it does not make remedies work. |
| Vital force | Illness is a disturbance of an invisible life energy that remedies restore. | No evidence such a force exists. |
| Miasms | Chronic disease stems from inherited or acquired underlying tendencies. | Not recognized by modern medicine or genetics. |
| Hering’s law of cure | Healing moves from inside out, top down, and in reverse order of appearance. | A traditional teaching, not a tested law. |
Our article on Hahnemann’s theory of miasms explains that idea in more depth.
The history of homeopathy
Samuel Hahnemann was born in Meissen, Germany, on April 10, 1755. He qualified as a physician at Erlangen in 1779. Disillusioned with the harsh medicine of his day, he earned much of his living by translating medical texts.
The turning point came in 1790. While translating a book by Scottish physician William Cullen, Hahnemann doubted its explanation of how cinchona bark worked against malaria. He took cinchona himself and reported symptoms resembling the fever it was used to treat. That experience shaped his “law of similars.”
Why homeopathy became popular
Context explains much of homeopathy’s early success. Encyclopaedia Britannica notes that many 19th-century patients saw it as a gentler option than the medicine of the time. That medicine included bloodletting, purging and heavy, mixed doses of drugs. A treatment that did nothing could genuinely leave patients better off than one that harmed them.
Hahnemann also stressed diet, fresh air and careful observation of each patient. Those habits were sensible regardless of his remedies. As scientific medicine developed effective vaccines, antibiotics and surgery, homeopathy’s relative advantage faded.
The later teachers
Several figures shaped the tradition after Hahnemann. Constantine Hering, a German physician who settled in the United States, gave his name to the “law of cure.” James Tyler Kent, a 19th-century American physician, wrote influential lectures and a symptom index called a repertory. William Boericke compiled a widely used pocket Materia Medica. In recent decades, Greek teacher George Vithoulkas has promoted the classical approach.
What is homeopathy made of? How remedies are prepared
Every remedy starts with a source substance. Plant sources include monkshood, pasque flower and poison ivy. Mineral sources include sulfur, salt and phosphorus. Animal sources include honeybee and snake venom. Some remedies, called nosodes, are made from diseased tissue or discharges.
Plant, mineral or animal material
Soaked in alcohol, or ground with lactose
1 part in 10 (X) or 1 part in 100 (C)
Shake vigorously; repeat steps 3 and 4
Drops onto sugar pellets or tablets
Hahnemann believed the shaking, called succussion, released a “dynamic” healing power from the substance. That belief is the core reason scientists consider homeopathy implausible. Once dilution goes far enough, the remaining liquid is chemically indistinguishable from the solvent.
Potencies: what the X, C and LM scales mean
The number and letter on a remedy label is its potency. It tells you how many dilution steps were used. This article explains the scale only. It gives no doses or potencies for treating any condition.
| Label | Dilution steps | Concentration of source | What it means in practice |
|---|---|---|---|
| Mother tincture (Q or Ø) | None | Full strength extract | Contains active substance. Can be toxic. |
| 3X (or D3) | 3 steps of 1:10 | 1 part per thousand | Still contains measurable substance |
| 6X | 6 steps of 1:10 | 1 part per million | Trace amounts may remain |
| 6C | 6 steps of 1:100 | 1 part per trillion | Extremely small traces at most |
| 12C | 12 steps of 1:100 | 1 part in 10 to the 24th power | Around the point where no molecule is likely to remain |
| 30C, 200C | 30 or 200 steps of 1:100 | Far beyond any molecule | Chemically just water, alcohol or sugar |
| LM (or Q) potencies | Steps of 1:50,000 | Very high dilutions | A later method described in the Organon’s 6th edition |
The 12C threshold comes from Avogadro’s number, about 6 × 1023. That is roughly how many molecules are in a standard amount of a substance. Dilute beyond that factor and, on average, not a single original molecule is left. Red rows in the table matter most for safety, because they can contain real amounts of toxic sources.
How a classical homeopathic consultation works
A classical first consultation is often long. The practitioner asks about physical symptoms, sleep, food cravings, fears and reactions to heat, cold and weather. They look for “modalities,” the factors that make symptoms better or worse.
Next, they look up the symptoms in a repertory, an index that lists remedies under each symptom. They then compare the shortlisted remedies in a materia medica, a reference book of remedy pictures. The aim is to find the single remedy whose picture best matches the whole person.
Homeopaths distinguish acute prescribing, for short illnesses, from constitutional prescribing, for a person’s long-term tendencies. This individualized method partly explains why some patients report feeling better. Long, attentive consultations can be supportive in themselves, regardless of the remedy.
The polychrests: homeopathy’s best-known remedies
Classical texts call the most widely used remedies polychrests, meaning “many uses.” The table summarizes how Boericke and Kent describe several of them. It records tradition only.
| Remedy | Source | Classical emotional and physical picture | Thirst | Modalities | Miasm link |
|---|---|---|---|---|---|
| Sulphur | The element sulfur | Warm, untidy, philosophical; itchy, burning skin | Drinks much, eats little | Worse heat, bathing, standing | Psora, its chief remedy |
| Pulsatilla | Pasque flower | Gentle, tearful, changeable; wants company | Thirstless | Worse warm rooms, better open air | Not fixed in classical texts |
| Lycopodium | Club moss spores | Outwardly confident, inwardly insecure; bloating | Prefers warm drinks | Worse late afternoon | Often linked to psora |
| Arsenicum album | Arsenic trioxide | Anxious, orderly, restless; chilly, burning pains | Small, frequent sips | Worse after midnight, better warmth | Not fixed in classical texts |
| Nux vomica | Poison nut seeds | Driven, irritable, oversensitive; digestive upset | Not characteristic | Worse cold, morning, stimulants | Not fixed in classical texts |
| Calcarea carbonica | Oyster shell | Steady, cautious, easily tired; chilly and sweaty | Craves cold drinks | Worse cold damp, exertion | Psora |
| Phosphorus | The element phosphorus | Open, sympathetic, fearful alone | Cold drinks | Worse lying on left side | Not fixed in classical texts |
| Natrum muriaticum | Table salt | Reserved, dwells on grief, dislikes consolation | Very thirsty | Worse sun and heat | Psora |
Compiled from Boericke’s Materia Medica and Kent’s lectures. These personality portraits are the tradition’s view and have not been validated by research.
Individual remedies are profiled in our remedies collection, each written as history and tradition.
Antidotes and remedy relationships
Classical texts also describe how remedies interact. An antidote is believed to cancel a remedy’s action. A complementary remedy is believed to complete another’s work. Some pairs are listed as incompatible, meaning the texts advise against using one after the other.
Many homeopaths also teach that strong smells can “antidote” remedies. Camphor, coffee and mint are the usual examples. These ideas exist only within homeopathic theory, and no research supports them.
Does homeopathy work? What the evidence shows
This is where tradition and research part ways most clearly. Several major independent reviews have reached the same conclusion.
The National Health and Medical Research Council found no health conditions with reliable evidence that homeopathy is effective. NCCIH cites this finding.
The House of Commons Science and Technology Committee found homeopathy no more effective than placebo, with implausible explanations.
Shang and colleagues compared 110 homeopathy trials with 110 matched conventional trials. Large, high-quality homeopathy trials showed effects compatible with placebo.
Cochrane reviews on specific uses point the same way. A 2015 review of Oscillococcinum for flu found low-quality evidence and no proven prevention benefit. A 2018 review of homeopathy for children’s respiratory infections found no evidence of benefit. You can read more in our article on homeopathy and the flu.
Occasionally, small trials report positive results. A 2026 systematic review on tonsillitis, for example, found some favorable trials. It rated all the evidence as low certainty and drew no firm conclusions. Our article on sore throat and tonsillitis covers that review in detail.
Why do people feel better after homeopathy?
Many users report real improvement, and that experience deserves an honest explanation. Most minor illnesses, such as colds and sore throats, improve on their own. People often take a remedy when they feel worst, so recovery follows naturally. Placebo effects are real and can ease how symptoms feel.
A long, caring consultation can also reduce stress and help people feel heard. None of this requires the remedy to have a specific effect. It does explain why personal experience and controlled research can point in different directions.
Is homeopathy safe? Regulation and real risks
How homeopathy is regulated
- United States, FDA: homeopathic products are regulated as drugs, and none is FDA-approved. In 2019, the FDA withdrew its 1988 enforcement policy. In December 2022, it finalized guidance using a risk-based approach to enforcement.
- United States, FTC: in 2016, the Federal Trade Commission said homeopathic health claims need the same competent and reliable scientific evidence as other products. Otherwise, marketing must clearly say there is no scientific evidence the product works.
- England, NHS: in November 2017, NHS England decided homeopathy should no longer be routinely prescribed.
- Canada: Health Canada requires nosode labels to state they are not vaccines or an alternative to vaccination.
The main risks
The biggest risk is indirect. NCCIH notes that substituting homeopathy for effective treatment has been linked to serious harm. Delaying care for an infection, asthma or a serious illness can turn a treatable problem into a dangerous one.
The second risk is that not every product is just water and sugar. NCCIH warns that some products labeled homeopathic contain substantial amounts of active ingredients. These can cause side effects and drug interactions. Two US cases show how this happens:
- Belladonna teething products, 2017: the FDA warned about homeopathic teething tablets that contained too much belladonna, a toxic plant.
- Zicam nasal products, 2009: the FDA warned about homeopathic zinc nasal gels and swabs after reports of lost sense of smell.
Liquid remedies can also contain alcohol. NCCIH notes that the FDA allows levels higher than in conventional drugs, which matters for children and people avoiding alcohol.
- Vaccines. Nosodes do not provide immunity.
- Medical care for infections, serious or worsening illness, or any emergency
- Prescribed medicines. Do not stop them without talking to your doctor.
- A doctor’s care during pregnancy or for babies and children
If you are unsure whether symptoms need care, contact a doctor or your local health advice line. In the UK, that is NHS 111.
Common misconceptions about homeopathy
- “Homeopathic means herbal.” It does not. Herbal products contain plant compounds in measurable amounts. Most homeopathic remedies do not.
- “Natural means safe.” Mother tinctures and low X potencies of toxic plants and minerals can cause harm.
- “It’s sold in pharmacies, so it must be tested.” No US homeopathic product has been FDA-approved or evaluated for effectiveness.
- “Nosodes are a gentle vaccine.” Health Canada and NCCIH both state they are not vaccine alternatives.
- “Feeling better proves it works.” Natural recovery and placebo effects explain most improvement in short illnesses.
Homeopathy glossary
| Materia medica | A reference book describing each remedy’s symptom picture |
| Repertory | An index listing remedies under each symptom |
| Proving | Giving a substance to healthy volunteers and recording their symptoms |
| Potentization | Repeated dilution and shaking |
| Succussion | The vigorous shaking step in potentization |
| Modality | Anything that makes a symptom better or worse |
| Polychrest | A remedy with a wide range of traditional uses |
| Nosode | A remedy made from diseased tissue or discharge |
| Miasm | Hahnemann’s term for an underlying tendency to chronic disease |
| Mother tincture | The undiluted starting extract |
For more on the tradition’s ideas and figures, browse our homeopathy history articles.
How to talk to your doctor about homeopathy
Many people use homeopathy without telling their doctor, often because they expect disapproval. Saying so openly is safer. Your doctor needs a full list of what you take to spot interactions and to read your symptoms correctly.
- Bring the actual product or a photo of the label, including the potency.
- Say what you are using it for and how long you have used it.
- Ask whether your symptoms need tests or treatment that a remedy cannot replace.
- Agree on a point when you would stop waiting and come back, such as a fever lasting several days.
A good doctor will discuss your choices respectfully. If they recommend a treatment, ask what evidence supports it. That is the same question this article asks of homeopathy.
Your one step before buying any homeopathic product
Turn the package over and read the potency on the label. If it says mother tincture, Q, or a low number with X or D, it may contain real amounts of the source substance. Show it to your pharmacist and ask about interactions with anything else you take.
Free download
Homeopathy Label Reader and Glossary (PDF)
One printable page: how to read X, C and LM potencies and spot labels that may contain active ingredients. It adds pharmacist questions and a quick glossary. No doses and no treatment advice.
This article describes the history, principles and research on homeopathy for educational purposes. It is not a guide to action and not an instruction to treat any illness. If you have a health concern, please see a doctor or qualified healthcare professional first. Never delay or stop medical treatment because of anything you read here.
Sources
- National Center for Complementary and Integrative Health. Homeopathy. nccih.nih.gov/health/homeopathy
- National Health and Medical Research Council (Australia). NHMRC Statement on Homeopathy, 2015. Summarized by the Royal Australian College of General Practitioners: racgp.org.au position statement on homeopathy
- UK House of Commons Science and Technology Committee. Evidence Check 2: Homeopathy, HC 45, February 2010. committees.parliament.uk/work/4566
- Shang A, et al. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. The Lancet 2005. pubmed.ncbi.nlm.nih.gov/16125589
- Mathie RT, Frye J, Fisher P. Homeopathic Oscillococcinum for preventing and treating influenza and influenza-like illness. Cochrane Database of Systematic Reviews 2015, CD001957. cochrane.org/evidence/CD001957
- Homeopathic medicinal products for preventing and treating acute respiratory tract infections in children. Cochrane Database of Systematic Reviews 2018, CD005974. pubmed.ncbi.nlm.nih.gov/30196554
- Perry R, et al. Homeopathy for tonsillitis: a systematic review. European Journal of Integrative Medicine 2026. University of Bristol research record
- US Food and Drug Administration. Homeopathic Drug Products: Guidance for FDA Staff and Industry, December 2022. fda.gov
- US Federal Trade Commission. Enforcement Policy Statement on Marketing Claims for OTC Homeopathic Drugs, 2016. ftc.gov (PDF)
- The Pharmaceutical Journal. NHS England publishes new prescribing guidance, November 2017. pharmaceutical-journal.com
- Health Canada. Homeopathic remedies are not substitute vaccines, March 2019. recalls-rappels.canada.ca
- Encyclopaedia Britannica. Homeopathy. britannica.com/science/homeopathy
- New York Medical College Library. Christian Friedrich Samuel Hahnemann biography guide. guides.library.nymc.edu
- Center for Research. Three over-the-counter cold products are too risky (FDA Zicam warning, 2009). center4research.org
- Hahnemann S. Organon of Medicine, 6th edition; The Chronic Diseases, 1828.
- Boericke W. Pocket Manual of Homoeopathic Materia Medica, 9th edition, 1927.
- Kent JT. Lectures on Homoeopathic Materia Medica, 1905.
