Homeopathy refers to a widely practiced method of medicinal self-healing. Homeopathic practitioners administer very small doses of therapeutic animal, plant, or mineral substances to cure a set of physical, mental, and emotional symptoms, as opposed to the conventional approach of curing a particular illness or "abnormality."

The roots of the word, homeopathy, are derived from Greek and roughly translate to "similar" and "feeling." One of the primary homeopathic principles is called the Law of Similars or "likes ... cured by likes." The homeopathic approach uses medicinal substances or remedies that temporarily exacerbate the symptoms the patient wishes to alleviate. According to the Law of Similars, the chosen substance produces the same signs and symptoms that the patient exhibits; these are the symptoms that would develop in a healthy subject receiving this substance (Jacobs and Moskowitz 1996). A second important homeopathic principle is that high dilutions of a single substance, called "potencies," produce therapeutic effects that imitate the body's self-healing mechanisms. These effects continue even when there are no remaining molecules of the initial substance. This causes a puzzling effect for most scientists and researchers (Jacobs and Moskowitz 1996; Kondrot et al. 2000; Schwartz et al. 2000).

Although homeopathy is popular, its practice remains controversial in large part because the high dilution mechanisms of action are largely unknown (Schwartz et al. 2000) and many of the studies to confirm efficacy have had conflicting results and have lacked methodological rigor.

Samuel Hahnemann, MD (1755-1843), a German physician and chemist, discovered the homeopathic principle as a result of an experiment in which he ingested a small dose of cinchona (Peruvian bark). He soon began to experience palpitations, aching bones, numbness, and other symptoms that he recognized as indicators of intermittent fever. These were the very symptoms that cinchona was supposed to cure. This was the beginning of a series of experiments dating from 1790 to 1810, in which Hahnemann demonstrated that substances derived from certain plants, animals, and minerals temporarily could cause a set of symptoms in healthy people. Conversely, he discovered that in extremely minute doses, these same substances cure the corresponding symptoms in sick people (Jacobs and Moskowitz 1996).

Although Hahnemann successfully treated and prevented a scarlet fever epidemic, bringing attention and fame to homeopathy, his methods and philosophy were ridiculed by conventional physicians prior to 1822. By the mid-1820s, he had published detailed symptomatology of more than 90 medicinal substances in six editions of his Materia Medica Pura, a document that was to become a widely respected treatise. Homeopathy flourished in Europe and the United States in the latter part of the 19th century. In the United States, homeopathy influenced the establishment of hospitals, medical schools, and asylums for the mentally ill (Jacobs and Moskowitz 1996).

Technical achievements in conventional medicine (such as surgery and microbiology), combined with the rising popularity of antibiotics and synthetic pharmaceuticals, as well as specific actions of the American Medical Association to discourage the practice of homeopathy in the United States, led to the decline of homeopathy in the early and mid-20th century (Jacobs and Moskowitz 1996).

Homeopathy has recently experienced a resurgence, which may be related to the crisis in health care and a renewed interest in alternative medicine and self-care. In the United States, homeopathic remedies listed in the Homeopathic Pharmacopoeia of the United States are recognized and regulated by the Food and Drug Administration (FDA) and are widely sold in pharmacies and health-food stores. Homeopathy is also popular in Europe, Latin America, and Asia. In Germany, one-quarter of all physicians use homeopathy; in France, approximately one-third of general practice physicians apply this method of healing. In India, the modality is practiced by more than 100,000 homeopaths and is used in the national health service (Jacobs and Moskowitz 1996).

Homeopathy is based on eight scientific principles:

• The most important law in homeopathy is the Law of Similars. In order for a substance to act homeopathically, the individual's symptoms have to be closely matched to the symptoms that the remedy can temporarily create. Otherwise, the remedy will not have the desired effect (Jacobs and Moskowitz 1996).
• Homeopaths who adhere to the classical Hahnemannian method employ a single remedy at a time in order to identify the best possible match with the patient's symptoms. Those who subscribe to this approach take care not to repeat the dosage too soon, if at all, in order to avoid interfering with the initial action of the remedy (Jacobs and Moskowitz 1996; Kondrot et al. 2000).
• The therapeutic dosage should be the lowest possible dose that creates the desired symptoms and minimizes side effects. If possible, remedies should not be repeated (Kondrot et al. 2000). Large dosages or dosages over an extended period of time should not be necessary and may even be counterproductive (Jacobs and Moskowitz 1996).
• Provings are experimental methods for studying the medicinal action of a particular substance (Jacobs and Moskowitz 1996). According to these methods, each homeopathic remedy represents the totality of observable responses of all the people to whom the particular substance has been administered. These provings have been carefully compiled and analyzed. Because the focus is on studying a single remedy and its effects, classically trained practitioners consider combination remedies to be untested and, thus, their effectiveness to be unproven (Kondrot et al. 2000).
• As with acupuncture and herbalism, homeopathy rests on the foundation that a vital force, or life energy, exists within each organism and is the source of health (Jacobs and Moskowitz 1996). Illness is a disruption of this energy (Kondrot et al. 2000). External symptoms associated with a condition or illness are the body's attempt to heal itself. Homeopathic remedies work to induce this self-healing process. It should be understood, however, that homeopathy is primarily a method of diagnosis and treatment rather than a philosophy. According to its founder it can, and should, be evaluated by how well it works (Jacobs and Moskowitz 1996; Kondrot et al. 2000).
• The principle of the Totality of Symptoms holds that illness is a composite of the physical, mental, and emotional responses of each patient (Jacobs and Moskowitz 1996). Determination of the most appropriate remedy is a function of assessing a person's principal physical symptoms as well as his or her mental and emotional symptoms. Treatment is highly individualized because the practitioner is interested in understanding how each person uniquely responds to a particular remedy (Kondrot et al. 2000).
• The Laws of Cure are based on the idea that human beings are integrated energy systems. As such, the practitioner must glean as much information as possible from the patient, including the timing of the first appearance of the symptoms, if and when any symptoms occur in clusters, and any possible association between clusters of symptoms and the patient's state of health and functionality (Jacobs and Moskowitz 1996). In recovery, symptoms move throughout the body. There are four directions of movement: from vital organs to less vital organs, from interior to exterior, from head to foot, and in the reverse order in which they appeared (Jacobs and Moskowitz 1996; Kondrot et al. 2000).
• Homeopathic remedies are prepared according to the Law of Dilution and Succussion. Remedies are diluted to produce fewer adverse side effects while still maintaining their medicinal properties. They are then succussed, or shaken, to stimulate the active ingredients in the solution (Kondrot et al. 2000). Plants, animal products, and other soluble substances are diluted in alcohol and insoluble remedies are pulverized and diluted with lactose. The preparations are vigorously shaken to form the "mother tinctures," which are further diluted to potencies of 1 to 10 (noted as "X") or 1 to 100 (noted as "C"). Successive rounds of dilution and agitation of the medium are performed to yield potencies of 2X, 3X, 4X or 2C, 3C, 4C and on, up to 50,000C (noted as 50M) (Jacobs and Moskowitz 1996).

The homeopathic mechanism of action, particularly with regard to the therapeutic effectiveness of high-dilution remedies, is not clearly understood (Dietz 1999). Some scientists familiar with developments in quantum physics believe that the electromagnetic energy in the homeopathic medicines interacts with the body in some manner. Physical chemistry researchers have hypothesized a "memory of water" theory, which holds that the process of diluting the remedies in water or alcohol causes a seemingly permanent change in the structure of the solution even after the medicine dissolves (Jacobs and Moskowitz 1996). The systemic memory resonance hypothesis is an attempt to explain how a solution can continue to have the therapeutic properties of the starting substance when molecules of the starting substance are no longer present. This theory holds that complex patterns of energy and information are stored in the body, specifically in physical, chemical, and biological systems. The thought is that information never disappears completely, even when a substance is withdrawn (Schwartz et al. 2000). Yet another hypothesis is that homeopathy works on a bioenergetic level to restore homeostasis (Kondrot et al. 2000).

The principle of similars is not as controversial as the high-dilution principle. It is, in fact, well accepted in certain areas of conventional medicine and scientific investigation (Schwartz et al. 2000).

The clinical procedure involves an extensive interview with the patient (uninterrupted by the practitioner as much as possible except for promptings for additional information). The purpose of the interview is to gather complete information about the physical, mental, and emotional condition of the patient. The initial visit also includes a physical examination and laboratory tests, if needed. The practitioner then prioritizes the reported symptoms, investigates further as needed, analyzes all the information, and makes a treatment recommendation (Jacobs and Moskowitz 1996).

The homeopathic remedy is available to patients in various preparations, including fluids, sucrose pellets, lactose tablets, mother tinctures, and ointments (Jacobs and Moskowitz 1996; Kondrot et al. 2000), as well as different levels of potencies (Jacobs and Moskowitz 1996). The patient's progress is re-evaluated after four to six weeks (Kondrot et al. 2000); he or she may need to try several remedies before an appropriate match is obtained (Jacobs and Moskowitz 1996).

Scientists are reluctant to conclude that homeopathic remedies are generally effective. To ascertain effectiveness, it is necessary to examine individual substances and their outcomes (Cucherat et al. 2000). Various studies and randomized clinical trials have considered the safety and/or efficacy of particular homeopathic remedies. Some have confirmed effectiveness; others have not (Dietz 1999).

A randomized controlled study, for example, found that the homeopathic remedy was as effective as the conventional approach for the treatment of vertigo. Both produced a reduction in the average frequency, duration, and intensity of vertiginous attacks. The homeopathic remedy was slightly superior in decreasing the frequency of such attacks (Weiser et al. 1998).

Studies published in the British Medical Journal (BMJ) and the Lancet have reported mixed results with homeopathic preparations of the herb Arnica montana. In 1991, the BMJ reported on four different studies in which the methodology proved to be unsound; thus, conclusions about efficacy could not be determined. However, in a 1997 meta-analysis published in the Lancet, homeopathic arnica was studied for treatment of pain, sprains, bruises, hematomas, hemarthrosis, and complications from surgery; six trials (of which three were good quality) suggested a positive clinical effect, one trial reported neutral results, and three had negative clinical outcomes (Dietz 1999).

A randomized, controlled trial published in the Lancet showed that use of dilute preparations of primary allergens brought about short-term relief in patients with allergy-induced asthma (Reilly et al. 1994). A clinical trial evaluating a homeopathic remedy for pain associated with rheumatoid arthritis showed improvement in the homeopathy group (Dietz 1999). Results of clinical trials also suggest that homeopathic remedies may be effective for fibrositis (fibromyalgia) (Fisher et al. 1989) and for allergies, especially hay fever (Reilly et al. 1986). According to results from another study, homeopathic remedies may be more effective than pharmaceuticals in reducing the number of days in pain, shortening the duration of treatment, and preventing the recurrence of otitis media (Freise et al. 1997).

Authors of a meta-analysis of clinical trials found that favorable results could be obtained when treating the following conditions homeopathically: dystocia, postoperative pain, knee-joint hematomas, sinusitis, diarrhea in children, and influenza (Cucherat et al. 2000). Homeopathy may also be useful in treating headaches (Whitmarsh 1997), irritable bowel syndrome (Ullman 1995), and osteoarthritis (van Haselen and Fisher 2000), but these conditions require further study to confirm the efficacy of treatments.

Homeopathy may be useful as a therapy for disorders that do not respond well to conventional treatment. Some of these disorders include chronic fatigue syndrome, digestive problems, headache, hemorrhoids, insomnia, premenstrual syndrome, AIDS-related symptoms, other viral illnesses, recurring infections, multiple sclerosis, surgical wounds, fibroids, gallstones, and traumatic injury (Jacobs and Moskowitz 1996). Homeopathy may also be useful during pregnancy, when many pharmaceuticals are contraindicated, and for patients who are sensitive to, or who refuse to take, conventional medications (Kondrot et al. 2000).

Homeopathy is generally considered safe due to the extreme dilution of the remedies (Kondrot et al. 2000). Very few adverse events have been reported in the literature (Jacobs and Moskowitz 1996). Occasionally, homeopathy may lead to a temporary aggravation of the symptoms the remedy is intended to cure (Kondrot et al. 2000). There have also been rare reports of nausea and hand tremors from particular homeopathic remedies, as in the clinical trial for vertigo mentioned earlier (Weiser et al. 1998). One warning in the literature concerns homeopathic remedies that contain phosphorus or silica. These are alleged to be dangerous if used inappropriately. All homeopathic remedies should be discontinued once the presenting complaint has disappeared in order to minimize any possible risk of side effects or other problems (Kondrot et al. 2000).

Homeopathic treatments are considered to be safe, gentle, cost-effective, and easy to administer (Jacobs and Moskowitz 1996; Kondrot et al. 2000). There are few absolute contraindications about this modality in the scientific literature (Kondrot et al. 2000). Because conventional medical treatment might be more relevant in certain circumstances, homeopathy is inappropriate for the treatment of chronic illness when the symptoms include advanced tissue damage, as in the case of cirrhosis of the liver or severe cardiovascular disease (Jacobs and Moskowitz 1996). Homeopathy is also inappropriate for patients who are dependent on conventional medications such as corticosteroids, anticonvulsants, or antipsychotic medications (Jacobs and Moskowitz 1996), or patients taking antibiotics or chemotherapeutic drugs (Kondrot et al. 2000). Homeopathy is not a substitute for patients who need conventional medical treatments such as emergency surgery or treatment for fractures (Jacobs and Moskowitz 1996). In addition, certain substances and treatments can neutralize a homeopathic remedy. Neutralizers include coffee, certain herbs, recreational drugs, the use of acupuncture, and vibrations due to dental drilling (Kondrot et al. 2000).

Many health problems can be treated with homeopathy when a trained professional employs the appropriate diagnostic approach and therapeutic guidance. In addition to conditions mentioned in the Clinical Applications section, there are remedies for rashes, wounds, and chronic skin problems; emotional issues and psychological disorders; menstrual and menopausal symptoms; bites and stings of any type; bacterial, viral, and fungal infections; childbirth, breast feeding, and postpartum care; bone, tendon, connective tissue, joint, muscle, and ligament strains and injuries; pain of any kind; gastrointestinal, nerve, pulmonary, renal, eye, ear, pelvic, bone, and respiratory disorders. Homeopathy may also provide symptomatic relief and adjunctive care for incurable conditions, such as cancer, diabetes, AIDS, and schizophrenia (Kondrot et al. 2000).

The efficacy of homeopathic medicine as a modality remains controversial and will probably continue to be so until more rigorous methodological studies prove its mechanism of action and effectiveness (Cucherat et al. 2000). At present, the primary scientific question concerns the dilution process used for homeopathic remedies (described above in the section on Scientific Principles). The dilution process reduces the concentration of the original substance to below Avogadro's number, the point at which molecules continue to physically exist (Jacobs and Moskowitz 1996).

Overall, there appears to be a significant amount of anecdotal evidence in favor of homeopathy (Jacobs and Moskowitz 1996) and, depending on the remedy, there may currently exist some scientific confirmation as well. More clinical trials and scientific studies are needed.

Training, Certification, and Licensing

There are numerous schools and training programs for homeopathy. The Council for Homeopathic Certification is the only organization in the United States that certifies competency in homeopathy regardless of whether the practitioner has been medically trained. Its certification designation is CCH (Certified in Classical Homeopathy). Licensure requirements for homeopathy vary from state to state. Homeopathy is currently licensed in Arizona, Connecticut, and Nevada. In most other states, lay homeopaths can practice in an unlicensed capacity. For doctors, homeopathy is viewed as a diagnosis and treatment modality and as such, it is included in the license of physician. There is currently a movement to get all homeopaths certified by the Council for Homeopathic Certification (Kondrot et al. 2000).

For more information, contact the Council on Homeopathic Certification in San Francisco, California or visit them on the web at www.homeopathy-council.org; the National Center of Homeopathy in Alexandria, Virginia at 703-548-7790 or visit the center on the web at www.homeopathic.org; Homeopathic Educational Services in Berkeley, California at 510-649-0294 or visit them on the web at www.homeopathic.com; and the International Foundation for Homeopathy at 2366 Eastlake Ave. E, Suite 325, Seattle, WA 98102.

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