Pharmacists should be aware of the facts and fiction surrounding the use of homeopathic products.
The practice of homeopathy started 200 years ago, and despite considerable criticism and controversy, many people find relief from homeopathic remedies. Advocates of homeopathy cite its lack of adverse effects, its patientcentered approach, and its low cost as reasons for its popularity. Critics say homeopathy is quackery and unfounded in science. Which is it?
Origins and Theories
Homeopathy is a traditional form of medicine that is significantly different from allopathy, the treating of disease using drugs and biologics that produce effects different from those produced by the disease under treatment. It is based on 3 principles.
The first principle, and the reason it is called “HOMEOpathy,” is the theory that “like treats like,” or “similitude.” Homeopathy’s founding father, German doctor Samuel Hahnemann (1745- 1843), noticed that consuming Peruvian Cinchona tree bark induced malaria-like symptoms—and also cured malaria. He surmised that plant, animal, or mineral substances that cause a particular symptom set in healthy people, when administered in homeopathic dosage forms to ill people exhibiting those symptoms, will cure the symptoms. He experimented with mercury, arsenic salts, and nux vomica, among other things. His experiments are considered some of the earliest work in toxicology. Although Hahnemann formed no explanation of a possible mechanism, the “like treats like” principle was born.1
Second, homeopaths believe that very small doses of plants, animal tissue, or minerals actually can cure, and their remedies gain potency with dilution. Often the substances used to make homeopathic remedies are toxic at undiluted concentrations. Homeopaths call the diluting process “succession.” They vigorously shake the original substance with alcohol or water to activate and ‘‘potenize’’ the substance. Conventional analysis is often unable to detect any molecules of original solute in the finished product. This is the theory with which most health care providers who believe in dose-response and evidence-based medicine have the most concern; they consider the product to be lacking in active ingredients.1,2
Third, homeopaths believe in individualized therapy based on symptoms. They believe that each patient has a unique personality and symptom pattern of illness. Homeopathic practitioners select remedies to address the patient’s specific symptom variation. In this way, homeopathy does not differ from traditional medicine—good allopaths do the same.
Can homeopathy’s extreme dilutions produce a real clinical, biologic, and pharmacologic effect? Pharmacists’ training and experience may lead us to dismiss these products. Recent science, however, has been able to identify particles and processes that, until just recently, seemed infinitesimal, and in fact were immeasurable. (Consider Phase 0 investigational studies—oncology researchers can now give volunteers a few tiny, subtherapeutic doses of an investigational agent and monitor whether the agent reaches the tumor, how it circulates and distributes throughout the body, and how cancer cells respond.3
) These cellular-level advances may someday explain how some homeopathic products work.2
Currently, a few theories have been advanced.
Do They Work?
The evidence for homeopathic remedies is at best conflicted. Some trials indicate they are no better than placebo, whereas others find that they work. Six (or 7, depending on how you count) metaanalyses of homeopathic remedies are often cited:
Kleijnen et al4 found that 81 of 107 trials reported positive results, but acknowledged some poor trial quality and design.
Boissel et al5 conducted meta-analysis and reported to the European Commission in 1996, indicating that “patients treated with homeopathy had greater beneficial effects than those who took the placebo.”
Linde et al6 reviewed 189 placebocontrolled randomized or double-blind studies, and found 74 with positive results. Again, study quality was cited as a limitation. The authors reanalyzed the results in 1999,7 including 89 of the best studies, and found homeopathy performed better than placebo.
Clausius et al8 found that homeopathy’s clinical effects were not completely due to placebo effect.
Cucharat et al9 whittled 118 studies down to 16 of the best, and found homeopathy performed better than placebo.
Shang et al10 found 110 studies, 8 of which met their inclusion criteria, and attributed all clinical effects to placebo effect.
Some people suspect that homeopathy works because many conditions improve naturally, and the homeopathic remedy does neither harm nor good. Others cite placebo or nocebo effect, both of which can be powerful.11
Patients’ conditions may respond to the consultation and increased attention alone. The homeopath may be better able to convince patients to implement lifestyle changes.
Some patients like homeopathic remedies. A study conducted in England, where homeopathy is covered by the National Health Service,12
found that 44% of a homeopathic clinic’s patients had suffered with a medical problem for more than 5 years; help from primary or secondary care providers was unsatisfactory. Overall, 73% of patients (n = 183) who were treated with homeopathic remedies reported symptoms, activity, and well-being improvement at 6 months. Approximately 25% of patients reduced their conventional medications at 6 months.12
Homeopathy often appeals to patients when conventional treatment fails or causes intolerable adverse effects. Homeopathic prescriptions are also inexpensive, often significantly less than a conventional prescription’s cost.12
Implication for Pharmacists
Pharmacists may field questions from patients about homeopathic medications. Some common products are listed in the Table.13-15
The best approach is to answer all questions respectfully and truthfully. Remember that data are mixed, yet some rigorous studies have shown that certain remedies work. It appears that the safest, most effective use of homeopathy is in conjunction with traditional care. Dismissing positive patient experience as a delusion or placebo effect is ill-advised.
It is always best to keep an open mind where patients and treatments are concerned. Many allopathic medications have unknown mechanisms of action, and some have never been proved effective. Ultimately, each pharmacist may not need to know intricate details of homeopathy, but should know the general principles.
Clathrates (also known as IE crystals and icelike crystals). Some researchers propose water clusters called clathrates may explain how homeopathic dilutions transfer a substance’s medicinal properties to a vehicle solvent. Clathrates grow like crystals during the dilution process, and the evidence for their presence is measured by oscillatory effects on the vehicle fluid.
Electromagnetic frequency. Some researchers believe that homeopathic remedies alter the strength of electromagnetic energy fields surrounding and permeating every living cell.
Hormesis. Also known as the Arndt-Shulz Law, hormesis describes a stimulatory effect caused by small amounts of potentially toxic substances. The theory was first proposed by Stebbing in 1982. This theory has become progressively more useful to the fields of toxicology, pharmacology, and risk assessment, where low-dose effects are of interest.
Adapted from references 4-12.
Ms. Wick is a visiting professor at the University of Connecticut School of Pharmacy and a freelance writer from Virginia.
1. Erlewyn-Lajeunesse M. Homeopathic medicines for children. Arch Dis Child.
2. Boiron C. Homeopathy, a tremendous opportunity for medicine! Eur J Intern Med
. 2011;22:117-8; author reply 118-119.
3. American Cancer Society. Phase 0 clinical trials: exploring if and how a new drug may work. www.cancer.org/treatment/treatmentsandsideeffects/clinicaltrials/whatyouneedtoknowaboutclinicaltrials/clinical-trials-what-you-need-to-know-phase0. Accessed September 7, 2012.
4. Klenijnen J, Knipschild P, Riet G. Clinical trials of homeopathy. BMJ
5. Boissel JP, Cucherat M, Gooch M, Haugh MC. Evidence of clinical efficacy of homeopathy: a meta-analysis of clinical trials. Eur J Pharmacol
6. Linde K, Clausius N, Ramirez G, et al. Are the clinical effects of homeopathy placebo effects? a meta-analysis of placebo-controlled trials. Lancet
7. Linde K, Scholz M, Ramirez G, Clausius N, Melchart D, Jonas WB. Impact of study quality on outcome in placebo-controlled trials of homeopathy. J Clin Epidemiol
8. Clausius N, Eitel F, Hedges VL, et al. Are the clinical effects of homoeopathy placebo effects? a meta-analysis of placebo controlled trials. Lancet
9. Cucherat M, Haugh MC, Gooch M, Boissel JP; Homeopathic Medicines Research Advisory Group. Evidence of clinical efficacy of homeopathy: a meta-analysis of clinical trials. Eur J Clin Pharmacol.
10. Shang A, Huweiler-Muntener K, Nartey L, et al. Are the clinical effects of homeopathy placebo effects? comparative study of placebo-controlled trials of homeopathy and allopathy. Lancet
11. Zanni GR, Wick JY. The power of placebo: current theories and strategies. Consult Pharm
12. Bawden S. Running an NHS community homeopathy clinic - 10-year anniversary 2001-2011. Homeopathy
13. Thompson EA, Bishop JL, Northstone K. The use of homeopathic products in childhood: data generated over 8.5 years from the Avon Longitudinal Study of Parents and Children (ALSPAC). J Altern Complement Med
14. Simpson N , Roman K. Complementary medicine use in children: extent and reasons: a population-based study. Br J Gen Pract
15. Terry R, Perry R, Ernst E. An overview of systematic reviews of complementary and alternative medicine for fibromyalgia. Clin Rheumatol
16. Anagnostatos GS. Small water clusters (clathrates) in the preparation process of homeopathy. In: Endler PC, Schulte J, eds. Fundamental Research in Ultra High Dilution and Homeopathy
. Dordrecht, The Netherlands: Kluwer Acad Publ; 1998:121-128.
17. Calabrese EJ. Toxicology rewrites its history and rethinks its future: giving equal focus to both harmful and beneficial effects. Environ Toxicol Chem
18. Anagnostatos GS, Pissis P, Viras K, Soutzidou M. Theory and experiments on high dilutions. In: Ernst E, Hahn EG, eds. Homeopathy–A Critical Appraisal
. Oxford, UK: Butterworth-Heinemann, Reed Educational and Professional Publishers Ltd; 1998:153-166.
19. Davenas E, Beauvais F, Amara J, et al. Human basophil degranulation triggered by very dilute antiserum against IgE. Nature
20. Allegre CJ, Provost A, Jaupert C. Oscillatory zoning: a pathological case of crystal growth. Nature
21. Stebbing ARD. Hormesis – the stimulation of growth by low levels of inhibitors. Sci Total Environ
22. Matsumoto J. Molecular mechanism of biological responses to homeopathic medications. Med Hypotheses
23. Coghlan A. Is this the trick that proves homeopathy isn’t hokum? common sense says it shouldn’t work, but scientists now agree that something weird happens when you add water. New Sci.
24. Calabrese EJ. Hormesis: improving predictions in the low-dose zone. EXS