Homeopathy was developed by a German physician named Samuel Hahnemann in the early 1800’s. Hahnemann examined the potential of substances to ‘cure’ symptoms that he produced in human healthy subjects. Hahnemann believed the body had its own intelligence and an innate ability to heal.
The exact mechanism of how homeopathy works isn’t known. It is suspected that homeopathic medicine works by a mechanism of action that is said to tune the patient’s vital force which has become unbalanced as a result of disease. Homeopathy is similar to Chinese medicine in that is considered an energy medicine that influences the body much the same as Chinese medicine has influence over the energy channels/meridians of the body.
Homeopathy’s efficacy is unsupported by the collective weight of modern scientific research. Because of this, the effectiveness of homeopathy has been in dispute since its inception.
Meta-analyses, in which large groups of studies are analyzed and conclusions drawn based on the results as a whole, have been used to evaluate the effectiveness of homeopathy. Early meta-analyses investigating homeopathic remedies showed slightly positive results among the studies examined, but such studies have warned that it was impossible to draw firm conclusions due to low methodological quality and difficulty in controlling for publication bias in the studies reviewed.
In 2001, a meta-analysis of clinical trials on the effectiveness of homeopathy concluded that earlier clinical trials showed signs of major weakness in methodology and reporting, and that homeopathy trials were less randomized and reported less on dropouts than other types of trials.
In 2002, a review of systematic reviews found that higher-quality trials tended to have less positive results, to the point that those results were clinically irrelevant. Also, when taking collectively all the systematic reviews, there was no convincing evidence that any homeopathic remedy had better effects than placebo, and current evidence did not allow to recommend its usage in clinical treatment.
In 2005, a systematic review of the representation of homeopathy in the medical literature suggested that mainstream journals had a publication bias against clinical trials of homeopathy that showed positive results, and the opposite was the case for complementary and alternative medicine journals.
The authors suggested that this could be due to an involuntary bias, or otherwise a submission bias, in which positive trials tend to be sent to CAM journals and negatives ones to mainstream journals. Reviews in all journals approached the subject in an apparently impartial manner, though most of the reviews published in CAM journals made no mention of the plausibility of homeopathy, whereas 9 out of 10 reviews in mainstream journals mentioned a lack of plausibility of homeopathy in the introduction.
In 2005, The Lancet medical journal published a meta-analysis of 110 placebo-controlled homeopathy trials and 110 matched medical trials based upon the Swiss government’s Program for Evaluating Complementary Medicine, or PEK. The study concluded that its findings were compatible with the notion that the clinical effects of homeopathy are nothing more than placebo effects.
A 2006 meta-analysis of six trials evaluating homeopathic treatments to reduce cancer therapy side-effects following radiotherapy and chemotherapy found “encouraging but not convincing” evidence in support of homeopathic treatment. Their analysis concluded that there was “insufficient evidence to support clinical efficacy of homeopathic therapy in cancer care”.
A 2007 systematic review of homeopathy for children and adolescents found that the evidence for attention-deficit hyperactivity disorder and childhood diarrhea was mixed. No difference from placebo was found for adenoid vegetation, asthma, or upper respiratory tract infection. Evidence was not sufficient to recommend any therapeutic or preventative intervention.
The Cochrane Library found insufficient clinical evidence to evaluate the efficacy of homeopathic treatments for asthma, dementia, or for the use of homeopathy in induction of labor. Other researchers found no evidence that homeopathy is beneficial for osteoarthritis, migraines, or delayed-onset muscle soreness.
Following this flurry of research and analysis, health organizations such as the UK’s National Health Service, the American Medical Association, and the FASEB have issued statements of their conclusion that there is no convincing scientific evidence to support the use of homeopathic treatments in medicine.
One of the reasons that homeopathy is not always suitable for the treatment of mental health is due to a phenomenon call “aggravation.” Aggravation in homeopathic medicine is the worsening of the condition of the patient. Although it is common occurrence in the practice of medicine in general, the worsening of the clinical features of psychiatric disorders like depression and schizophrenia are a cause for significant concern. In severe cases of aggravation, the phenomenon could be permanent and even lethal. Because of this, homeopathic medicine may be better suited for milder emotional conditions as opposed to more serious psychiatric disorders, as is the case with many complementary and alternative therapies.