Homeopathy is based on the concept of “treating like with like” (in Latin similia similibus curentur). Homeopathic treatment aims to stimulate and direct the body’s self-healing capacity by triggering a reaction. The body reacts to stimuli, which have physiological effects (drugs or toxins) by attempting to maintain homeostasis (a stable internal environment). Homeopathy makes therapeutic use of this effect.
Scientific scepticism about homeopathy arises from its use of highly dilute medicines. There is a substantial body of research on this issue: a review of basic research on highly dilute homeopathic medicines found 98 replicated experiments, over 70% of replications were positive. Methods used to prepare homeopathic medicines are remarkably similar to some used in cutting-edge nanotechnology and there is growing evidence that nanoparticles play a crucial role in the action of homeopathic medicines.
The research literature includes preclinical and clinical evidence of the effectiveness of homeopathy including historical, observational, comparative effectiveness and randomised clinical trial evidence of good outcomes, greater safety, patient acceptance, accessibility and cost-savings. Homeopathy is often used “to treat the patient, not the disease” strengthening host defences and resilience rather than killing microbes or blocking pathophysiological processes. Here there is overlap with other areas of pharmacology and toxicology including the widely observed phenomenon of hormesis (the paradoxical, stimulatory or beneficial effects of low doses of toxins). A hormetic dose response curve is non-linear: J shaped with a linear dose response relationship at high doses (the shaft) but a reversed dose response, ie beneficial or stimulatory (the hook) at low dose. Over 10,000 experiments demonstrating hormesis and important therapeutic implications have been identified.
THE PUBLIC HEALTH IMPLICATIONS OF HOMEOPATHY
Polypharmacy (the use of multiple drugs), particularly in the elderly is a major challenge to medicine. This includes opiate analgesics (painkillers), psychotropic drugs (including tranquillisers, antidepressants and sleeping tablets) and antibiotics. The overuse of antibiotics has led to a massive global crisis of antimicrobial resistance: we are running out of effective antibiotics. There is strong research evidence that the integration of homeopathy into medical practice reduces the use of all these hazardous groups of drugs.
The largest comparative effectiveness study of homeopathy published to date is the EPI3 study. A nationwide study in France, coordinated by the Department of Pharmacoepidemiology at the University of Bordeaux, it included 6,379 patients at 804 medical practices. It compared treatment outcomes for patients attending conventional, homeopathic, and mixed practice family physicians in musculoskeletal conditions, upper respiratory tract infection, sleep disorders, anxiety, and depression in terms of clinical benefit, medical care and medication, adverse effects, and loss of therapeutic opportunity. Patients did not differ between groups except for the chronicity of their illness, which was greater in the homeopathic group. Patients treated by homeopathic physicians showed a similar clinical progression but took about half the amount of non-steroidal anti-inflammatory drugs (NSAIDs) compared to conventionally-treated patients, with fewer NSAID-related adverse events and no loss of therapeutic opportunity.
Another study in the EPI3 series yielded an analogous result, showing that patients who consult family physicians certified in homeopathy used significantly less antibiotics and antipyretic/anti-inflammatory drugs for upper respiratory tract infections than those who attended family physicians who prescribe only conventional medications, with similar outcomes. This finding is of considerable public health importance since antimicrobial resistance is now a major global problem. One of its main causes is overuse of antibiotics for upper respiratory tract infections. Similar results were found in anxiety, depression and sleep disorders.
COMPARATIVE EFFECTIVENESS RESEARCH
Comparative effectiveness research examines the effectiveness of treatments in real-world situations, as opposed to the artificial conditions often imposed in randomized controlled trials, comparing outcomes in groups of patients (often known as cohorts) receiving different treatments. There are several such studies of homeopathy, comparing outcomes in various groups of patients attending conventional family physicians, and family physicians who integrate homeopathy in their practice, including those below.
A multinational comparative effectiveness study 30 doctors, at six clinical sites in four countries, including the UK, treating patients with acute respiratory problems. Response at 14 days was 82.6% for homeopathy compared to 68% for conventional treatment. The rate of adverse events for conventional treatment was 22.3%, versus 7.8% for homeopathy. A replication of this study included 1,577 patients, of whom 857 received homeopathic and 720 conventional treatment: improvement was significantly faster with homeopathy.
Trichard et al compared “homeopathic strategy” against “antibiotic strategy” in routine medical practice in the management of recurrent acute rhino-pharyngitis in 499 children aged between 18 months and 4 years. Family physicians using homeopathy had significantly better results in terms of clinical effectiveness, complications, parents’ quality of life and time lost from work, for lower cost to social security.
SAFETY OF HOMEOPATHY
Physician and consumer confidence in the safety of homeopathy is justified. There is no evidence that homeopathic medicines cause serious or long-lasting harm. A systematic review of the safety of homeopathy, which included a comprehensive search of the Englishlanguage literature and enquiries with regulatory authorities, including FDA, concluded: “Homeopathic medicines may provoke adverse effects, but these are generally mild and transient; adverse effects of homeopathy are under-reported; there are cases of “mistaken identity” where herbal medicines were described as homeopathic. The main risks associated with homeopathy are indirect, relating to the prescriber rather than the medicine.”
Homeopathic medicines are made from plants, animals (or parts of animals) and other substances serially diluted and vigorously agitated during the manufacturing process. Twelve independent research laboratories in the U.S., France, Italy, Russia, and India have now found that homeopathic medicines studied contain various nanostructures, including source material, silica nanoparticles and gas nanobubbles heterogeneously dispersed in colloidal solution.
This work suggests that homeopathic medicines, like modern engineered nanoparticles, act by modulating the allostatic stress response network (allostasis is the process of restoring a stable internal environment), including cytokines, oxidative stress and heat shock proteins. Sceptics frequently claim that there is no scientific evidence for homeopathy. As this short paper has shown, this is untrue. Although, according to current scientific understanding, it is implausible that the very high dilutions used in homeopathy have effects which are not placebo, there is abundant evidence that they do. Homeopathy is geographically widespread and increasing in popularity. Clinical research and syntheses of such research show it to be safe and effective for a range of conditions. Integrating homeopathy in health care systems is associated with benefits including improved outcomes, less use of drugs including antibiotics, and economic benefits.