Clinical Trials

Clinical trials are experiments carried out on patients to compare the effects of treatments under highly controlled conditions. One type of clinical trial – the randomised controlled trial (RCT) – is considered by many scientists to be the ‘gold standard’ of research methods for determining whether medical treatments are effective, especially if the control group for comparison is a placebo and both patients and practitioners are blinded as to whether the treatment given is placebo or the test treatment. These are known as double blind – randomised controlled trials (DB-RCTs).

RCTs have been used to investigate various different aspects of homeopathy, such as how homeopathic medicines compare with placebo and how effective homeopathic treatment is for specific conditions.

“Up to the end of 2011, there have been 164 peer-reviewed papers reporting randomised controlled trials (RCTs) in homeopathy. This represents research in 89 different medical conditions. Of those 164 RCT papers, 71 (43%) were positive, 9 (6%) negative and 80 (49%) non-conclusive1”.

The fact that 80 trials were inconclusive highlights the need for changes in the way homeopathy research is conducted in future to ensure that meaningful results are generated from clinical trials. Three key factors for improving the clinical trial evidence base for homeopathy are2:

  • the need for larger scale trials with larger sample sizes (commonly prevented by a lack of funding)
  • the use of research methods that are better suited to the task of testing homeopathy as a complex individualised therapy (such as pragmatic trials which allow treatment by a homeopath as experienced in real world practice, to be compared)
  • assess the value of homeopathy across a wider range of illnesses with repetition in each condition.

Given that homeopathy is a holistic therapy (treating the person as a whole rather than treating specific diseases) it can appear contradictory to have research trials testing homeopathic treatment of specific medical conditions. There are three main reasons why researchers are performing clinical trials that assess how effective homeopathic treatment is for a specific disease, working through this apparent clash of philosophies:

  1. Patients considering seeing a homeopath often ask whether homeopathy can help with the health problem that is bothering them most (their chief complaint)
  2. When another medical professional refers a patient to a homeopath they may want to know what track record the therapy has in treating that specific disease
  3. The NHS provides the majority of medical services according to disease categories. So for homeopathy to be included in the range of services offered by specific departments, research needs to demonstrate that homeopathic treatment is effective in treating specific conditions.

Research in homeopathy is a wide field and clinical trials are just one of many different avenues being pursued by researchers world-wide to build the evidence base for homeopathy, particularly the evidence base for homeopathy in practice.

The British Homeopathic Association has prepared a comprehensive list of positive trials investigating specific medical conditions that can be accessed here

To date (2014), the conditions for which the majority of clinical trial findings have been positive for homeopathy are in allergies and upper respiratory tract infections (URTIs) as shown in the table below.

Condition Level of supporting evidence
Allergies and URTIs Systematic review3
Bronchitis One un-refuted RCT4
Ear infection (acute otitis media)

One un-refuted RCT5

Treatment comparison trial6

Hayfever (seasonal allergic rhinitis) Systematic reviews7-9
Influenza Systematic review10
Sinusitis RCTs11,12



1. Faculty of Homeopathy, Research summary.

2. Mathie, RT, et al., 2013. Randomised controlled trials of homeopathy in humans: characterising the research journal literature for systematic review. Homeopathy; 102:3-24

3. Bornhoft G, Wolf U, Ammon K, et al. Effectiveness, safety and cost-effectiveness of homeopathy in general practice – summarized health technology assessment. Forsch Komplementarmed 2006; 13 (2): 19-29

4. Diefenbach M, Schilken J, Steiner G, Becker HJ. Homeopathic therapy in respiratory tract diseases. Evaluation of a clinical study in 258 patients. Z Allgemeinmed 1997; 73: 308-14

5. Jacobs J, Springer DA, Crothers D. Homeopathic treatment of acute otitis media in children: a preliminary randomized placebo-controlled trial. Pediatr Infect Dis J 2001; 20: 177-83

6. Wiesenauer M, Ludtke R. A meta-analysis of the homeopathic treatment of pollinosis with Galphimia glauca. Forsch Komplementarmed Klass Naturheilkd 1996; 3: 230-6

7. Taylor MA, Reilly D, Llewellyn-Jones RH, et al. Randomised controlled trials of homoeopathy versus placebo in perennial allergic rhinitis with overview of four trial series. Br Med J 2000; 321: 471-6

8. Bellavite P, Ortolani R, Pontarollo F, et al. Immunology and homeopathy. 4. Clinical studies – Part 2. eCAM 2006; 3: 397-409.

9. Vickers A, Smith C. Homoeopathic Oscillococcinum for preventing and treating influenza and influenza-like syndromes (Cochrane Review). In: The Cochrane Library. Chichester, UK: John Wiley & Sons, Ltd. 2006

10. Friese K-H, Zabalotnyi DI. Homeopathy in acute rhinosinusitis. A double-blind, placebo controlled study shows the effectiveness and tolerability of a homeopathic combination remedy. HNO 2007; 55: 271-7

11. Zabolotnyi DI, Kneis KC, Richardson A, et al. Efficacy of a complex homeopathic medication (Sinfrontal) in patients with acute maxillary sinusitis: a prospective, randomized, doubleblind, placebo-controlled, multicenter clinical trial. Explore (NY) 2007; 3: 98-109

12. Friese K-H, et al. Homeopathic treatment of otitis media in children: comparisons with conventional therapy. Int J Clin Pharmacol Ther, 1997; 35: 296-301.