By Lynne Eldridge, MD 
Medically reviewed by Meredith Bull, ND
September 25, 2020

Homeopathic medicine, or homeopathy, is a form of complementary and alternative medicine that uses very small amounts of natural substances, which in higher amounts may cause a disease or symptom. This branch of medicine came into being in the 19th century and was used frequently at the time. Interestingly, the first studies using homeopathic remedies were done on healthy volunteers—similar to many clinical trials done today. While the use of homeopathy has fallen off with the advent of newer conventional treatments, there are over 2,000 substances that have been utilized as homeopathic treatments.

What exactly is homeopathic medicine, and how is it thought to work? Below, we look at what the studies say about its effectiveness, how this compares with traditional medical options, and the possible side effects and risks of these therapies.

The Theory Behind Homeopathic Medicine

The theory behind homeopathic medicine is that "like cures like," and that a substance that causes an illness in a healthy person might cure those symptoms in someone who is ill. It's believed by practitioners of homeopathy that a small amount of the substance which causes a disease will stimulate the body to heal itself. Though this may sound far-fetched, the theory is somewhat analogous to the basis of vaccination in modern day medicine: with immunizations, the exposure to a small amount of a killed or inactivated microbe can result in protection against developing the disease.

Homeopathic medicine is based on the theory that "like cures like." An example of homeopathy would be using a very dilute solution of coffee to treat insomnia.

The other theory underlying homeopathy is that of potentization. It's thought by practitioners of homeopathy that the more dilute an ingredient, the more potent it becomes. The thought is that diluting and agitating an ingredient activates the curative powers of the ingredient, thus enhancing its effect. Potency in homeopathic solutions is indicated by an X or C.

- X: For every dilution, one part of an ingredient is mixed with two parts water. For example, a 1X potency would be a solution that is one part ingredient and 9 parts water.

- C: Potency may also be described with a C. A 1C solution refers to a solution that is one part ingredient and 99 parts water.

Looking at potentization from a scientific standpoint, many homeopathic remedies may contain very few or no molecules of the ingredient (for example, in a 30C solution). Skeptics have described this as the equivalent of dissolving a tablet of Advil in the ocean and then drinking a few drops. In response, some proponents of homeopathy claim that the the amount of the ingredient itself is not what is important, but rather the energetics of the ingredient, which the dilution process activates to initiate a therapeutic effect on the body. In fact, the more dilute the homeopathic, the more potent it is believed to be.

Principles of Homeopathy

There are three main principles behind the practice of homeopathic medicine.

- The law of similars: The law of similars refers to the "like cures like" theory noted above.

- The principle of the single remedy: This principle holds that a single remedy should cover the physical, emotional, and mental symptoms of an illness combined.

- The principle of the minimum dose: Only a small amount of substance is first used in a few doses, followed by an infinitesimal amount over time.