Developed in Germany in the late 1700s, homeopathy is a medical system based on the principle that "like cures like" (the law of similars). A substance that, when given in large doses, causes a certain set of symptoms is believed to cure the same symptoms when it is given in minute to almost nonexistent doses. The minute dose is thought to stimulate the body’s healing mechanisms.
Treatments are based on the patient’s unique characteristics, including lifestyle, symptoms, and general health. Homeopathy aims to restore the flow of the body's energy; it is not based on principles of chemistry or physiology.
Remedies used in homeopathy are derived from naturally occurring substances, such as plant extracts and minerals. Extremely low concentrations are prepared in a specific way. The more dilute the homeopathic remedy, the stronger it is considered to be. Many solutions are so dilute that they contain no measurable molecules of the active ingredient. For example, 30C dilution is diluted 1 to 100 in 30 serial dilutions, resulting in a final dilution of 1 x 1060.
Homeopathic products are available over the counter or from a homeopathic provider.
Regulation of Homeopathy
In the United States, homeopathic remedies are regulated by the Food and Drug Administration (FDA), unlike botanical and nutritional supplements. Only homeopathic remedies that are approved by the FDA can be manufactured. Because so little active ingredient is left after dilution, active ingredients are tested before dilution.
The FDA exempts homeopathic remedies from several requirements that exist for other medications:
The identity and strength of each active ingredient do not have to be confirmed by a laboratory before the remedy is distributed.
Manufacturers of homeopathic products are not required to provide evidence of efficacy.
Homeopathic remedies have been exempted from limits on the amount of alcohol (the usual diluent) that they can contain.
However, the label is required to list the following:
Manufacturer
The term “homeopathic”
At least 1 indication
Instructions for safe use
Unless specifically exempted, the active ingredient and degree of dilution
Evidence for Homeopathy
The 2 primary principles of homeopathy are "like cures like" and diluting makes preparations stronger. A preparation diluted so much that it has no active ingredient that can produce physiologic effects (other than those of a placebo) is biologically and chemically implausible. However, some proclaimed homeopathic preparations do contain active ingredients in concentration sufficient to have physiologic effects.
Efficacy of homeopathic remedies for various disorders has been extensively studied. Multiple systematic reviews and meta-analyses, performed in several countries, have found either no evidence or a lack of high-quality evidence to support the efficacy of homeopathic remedies for any of over 60 different indications (1–4).
However, for some clinical conditions for which conventional medical therapies are limited, such as for fibromyalgia, homeopathy might be considered given data from small studies of potential symptom relief and lack of harm (5, 6).
Evidence references
1. Ernst E. Homeopathy: what does the "best" evidence tell us? Med J Aust.192(8):458–60, 2010. doi:10.5694/j.1326-5377.2010.tb03585.x
2. United Kingdom's House of Commons Science and Technology Committee. Homeopathy, 2010. Accessed October 5, 2025.
3. National Health and Medical Research Council. Effectiveness of homeopathy for clinical conditions: evaluation of the evidence. Accessed October 2023.
4. Mathie RT, Fok YYY, Viksveen P, et al.Systematic review and meta-analysis of randomised, other-than-placebo controlled, trials of non-individualised homeopathic treatment. Homeopathy. 108(2):88-101, 2019. doi: 10.1055/s-0038-1677481
5. Boehm K, Raak C, Cramer H, et al. Homeopathy in the treatment of fibromyalgia—a comprehensive literature-review and meta-analysis. Complement Ther Med. 22(4):731-42, 2014. doi: 10.1016/j.ctim.2014.06.005
6. Bell IR, Lewis DA 2nd, Brooks AJ, et al. Improved clinical status in fibromyalgia patients treated with individualized homeopathic remedies versus placebo.Rheumatology (Oxford). 43(5):577–582, 2004. doi: 10.1093/rheumatology/keh111
Uses of Homeopathy
Homeopathy is commonly used in Europe and India, largely because of a long history of use; as a result, the practice has become part of the culture.
Homeopathy has been used to treat various disorders, such as allergies, rhinitis and respiratory symptoms, digestive problems, musculoskeletal pain, and vertigo.
Possible Adverse Effects
Homeopathy is generally well tolerated and has few risks; rarely, an allergic or toxic reaction occurs.
Studies have tried to compare adverse effects of homeopathy and conventional medicine, but additional high-quality research is needed to standardize reporting and risk assessment (1). Clinicians should not assume that a homeopathic remedy taken by a patient is biologically inactive and thus could not have adverse effects. Some homeopathic remedies contain other active ingredients that can have physiologic effects. Additionally, the identification of a product as homeopathic might be erroneous because patients often use the term when referring to a dietary supplement they are taking. Also, the FDA allows some medicinal botanicals to be registered as homeopathic if they undergo a particular pharmaceutical process.
Pearls & Pitfalls
|
Possible adverse effects reference
1. Stub T, Kristoffersen AE, Overvåg G, et al. Adverse effects in homeopathy. A systematic review and meta-analysis of observational studies. Explore (NY). 18(1):114-128, 2022. doi:10.1016/j.explore.2020.11.008
