Homeopathy is based on the Principle of Similars which means “likes cure likes."
Homeopathy is based on the Principle of Similars which means “likes cure likes."1 This principle is founded on the belief that symptoms of a disease can be cured by small doses of an ingredient that produce the same symptoms when administered at higher doses to healthy people. For example, an ingredient that causes a runny nose would be used to relieve the same symptoms associated with the disease allergic rhinitis.
To achieve small doses, ingredients are diluted with purified water or alcohol. Two main dilution methods are used to manufacture homeopathic products; decimal and centesimal.2 The method utilized is listed on the product label with a number (indicating the number of times the ingredient was diluted) followed by an X or C to indicate the ratio of dilution (1/10 for X or 1/100 for C). Homeopathy believes the more dilute an ingredient can be and still exert an effect, the greater its potency. This means that homeopathic products could be so dilute they contain very little, if any, of the active ingredient.
Historically, homeopathic products have been manufactured and marketed on a small scale to meet the needs of a limited number of patients. More recently, sales of homeopathic products have increased with sales estimated at $450 million in 2003.2 Homeopathic products are available over-the-counter to treat a variety of minor ailments amenable to self-care (e.g., cough and cold, influenza, allergic rhinitis, teething, diaper rash, etc.).
Efficacy of homeopathic products is controversial. Because ingredients in homeopathic products are extensively diluted, to the point where they may no longer contain detectable levels of the active ingredient, efficacy is essentially the result of a placebo effect. A 2010 analysis concluded that the scientific evidence related to the efficacy of homeopathic products is similar to placebo.3 Homeopathic products, when used in accordance with labeled instructions, are generally considered safe. Due to the very small amount of active ingredient contained in homeopathic products, the risk for adverse effects and toxicity is low.
Homeopathic products are classified as drugs under the Food, Drug, and Cosmetic Act and must be included in the Homeopathic Pharmacopoeia of the United States (HPUS) to be marketed and sold in the United States (US).1 Inclusion in the HPUS does not indicate safety or efficacy for the intended use. All homeopathic products must follow FDA labeling requirements and be manufactured using Current Good Manufacturing Practices. Over-the-counter homeopathic products contain a “Drug Facts Label” similar to that of conventional nonprescription drugs, which can make them hard to differentiate for patients.
In November 2016, the Federal Trade Commission (FTC) issued an enforcement policy statement regarding marketing claims for over-the-counter homeopathic products.4 The statement explains that homeopathic products will be held to the same marketing claims related to efficacy and safety as conventional nonprescription drugs.4 The manufacturer must have scientific evidence for any health-related claims if the marketing states that a product can treat a specific condition. To date, most studies showing efficacy of homeopathic products utilized homeopathic theories and no studies using current scientific methods have been conducted. Therefore, marketing claims related to efficacy may be misleading for patients.
The announcement of this enforcement policy statement regarding marketing claims may help to decrease patient confusion related to safety and efficacy of homeopathic products as manufacturers update labeling to comply with the FTC regulations. The FTC plans to inspect homeopathic marketing claims contained on the label with more scrutiny to be sure manufacturers are not overstating claims that are scientifically proven.
For more information about homeopathic products, visit http://www.fda.gov/iceci/compliancemanuals/compliancepolicyguidancemanual/ucm074360.htm.
1. FAQs About Homeopathic Medicine. Consumer Healthcare Products Association Web site. http://www.chpa.org/homeopathic.aspx. Accessed November 30, 2016.
2. Ulbricht C. Common Complementary and Alternative Medicine Health Systems. In: Krinsky DL, Ferreri SP, Henstreet BA, Hume AL, Newton GD, Rollins CJ, Tietze KJ. Handbook of Nonprescription Drugs: An Interactive Approach to Self-Care. Washington, DC: American Pharmacists Association; 2015;996-998.
3. Ernst E. Homeopathy: What does the “best” evidence tell us? Med J Aust. 2010;192(8):458-460.
4. Enforcement Policy Statement on Marketing Claims for OTC Homeopathic Drugs. FDA website. https://www.ftc.gov/system/files/documents/public_statements/996984/p114505_otc_homeopathic_drug_enforcement_policy_statement.pdf. Accessed November 30, 2016.