The Food and Drug Administration (FDA) estimates that the market for homeopathic drugs is about $3 billion. In an effort to crack down on the industry, the FDA announced a new, risk-based approach to regulating homeopathic treatments.
Homeopathy is defined by the FDA as the practice of treating disease with remedies that have produced similar syndromes and conditions in healthy subjects. The FDA further defines a homeopathic drug as any drug listed in the Homeopathic Pharmacopeia of the United States, an addendum to it, or its supplements. The potencies of homeopathic drugs are specified in terms of dilution (e.g. 1/10) and must contain diluents commonly used in homeopathic pharmaceutics. Drug products containing homeopathic ingredients in combination with non-homeopathic active ingredients are not considered homeopathic drugs by the FDA.
Homeopathic drugs are often marketed to treat a wide variety of diseases and disorders, including cancer, dementia, and attention-deficit hyperactivity disorder. However, there is no evidence that they are effective.
Under the new guidelines, the FDA will regulate certain categories of homeopathic drugs it considers to be risky, such as drugs whose ingredients are potentially toxic or harmful, drugs that are not taken orally or topically, and drugs marketed to people with life-threatening conditions and "vulnerable populations" like children and the elderly.