The evidence for homeopathy

There is a growing body of clinical evidence to show that homeopathy has a positive effect.

Randomised placebo-controlled trials

The widely accepted method of proving whether or not a medical intervention works is called a randomised controlled trial (RCT). One group of patients, the control group, receive placebo (a “dummy” pill) or standard treatment, and another group of patients receive the medicine being tested. The trial becomes double-blinded when neither the patient nor the practitioner knows which treatment the patient is getting. RCTs are often referred to as the “gold standard” of clinical research.

Up to the end of 2014, a total of 104 papers reporting good-quality placebo-controlled RCTs in homeopathy (on 61 different medical conditions) have been published in peer-reviewed journals. 41% of these RCTs have reported a balance of positive evidence, 5% a balance of negative evidence, and 54% have not been conclusively positive or negative. For full details of all these RCTs and more in-depth information on the research in general, visit the research section of the Faculty of Homeopathy’s website. Also, see 2-page evidence summary with full references.

The above figures are strikingly similar to data obtained from an analysis of 1016 systematic reviews of RCTs (and therefore of many more than that number of RCTs) in conventional medicine: 44% of the reviews concluded that the interventions studied were likely to be beneficial (positive); 7% concluded that the interventions were likely to be harmful (negative); and 49% reported that the evidence did not support either benefit or harm (non-conclusive). [El Dib RP, Atallah AN, Andriolo RB (2007). Mapping the Cochrane evidence for decision making in health care. Journal of Evaluation in Clinical Practice; 13:689–692.]

Systematic reviews

The most solid evidence for a treatment comes from critically assessing more than one RCT in a carefully defined way. This is known as a systematic review. Six out of seven major systematic reviews of RCTs in homeopathy have concluded (with important caveats) that homeopathy has an effect greater than placebo.  Systematic reviews of RCTs in specific medical areas have presented positive conclusions for homeopathy in six: childhood diarrhoea, hay fever, post-operative ileus, respiratory tract infection, rheumatic diseases and vertigo (see Faculty of Homeopathy website for details).

For full details of all 104 placebo-controlled RCT papers and more in-depth information on the research, visit the research section of the Faculty of Homeopathy’s website.  This includes details of those RCTs that were either negative or non-conclusive. Our own systematic review programme is providing further insight into these research findings.

Difficulties and opportunities with RCTs

The RCT model of measuring efficacy of a drug poses some challenges for homeopathic research. In homeopathy, treatment is usually tailored to the individual. A homeopathic prescription is based not only on the symptoms of disease in the patient but also on a host of other factors that are particular to that patient, including lifestyle, emotional health, personality, eating habits and medical history. The “efficacy” of an individualised homeopathic intervention is thus a complex blend of the prescribed medicine together with the other facets of the in-depth consultation and integrated health advice provided by the practitioner; under these circumstances, the specific effect of the homeopathic medicine itself may be difficult to quantify with precision in RCTs.

Nevertheless, in the first phase of our systematic review programme, examining placebo-controlled trials of individualised treatment across a total of 24 medical conditions, we observed a small overall effect of homeopathy that was statistically significantly greater than that of placebos. These findings cautiously suggest that prescribed homeopathic medicines do have specific treatment effects, at least in a majority of the conditions included in our analysis.

An alternative research approach, which the majority of researchers have adopted, is the “one drug fit all patients” type of RCT, akin to a conventional drug trial. Such trials are capable of quantifying efficacy of the homeopathic “drug” under investigation, but they may yield results that are of questionable relevance to the practice of homeopathy in the “real world”. This concern is also being examined in the BHA’s programme of systematic reviews.

Non-randomised studies

There are other types of study that form part of the evidence base for any medical intervention. Clinical outcome studies record the patient’s self-reported response after treatment. Studies of this kind are neither randomised nor controlled. Although they lie near the lower end of the “hierarchy” of research evidence, study designs such as these can reflect how homeopathy is working in practice and indicate where RCT research might be targeted.

The experience of patients

Many patients referred for homeopathic treatment have a complexity of health problems. They may suffer from more than one disease. They could be young children or elderly people. They may be pregnant. None of these sorts of patients would be accepted for a drug trial in conventional medicine, so their reactions to treatment are not reflected in the results of RCTs. The recording of clinical data from everyday practice reflects the experiences of real patients and is becoming an increasingly valued part of evidence-based medicine. View results from the homeopathic hospitals.

There are 21 non-randomised studies that have focused on a particular medical condition or set of conditions.

References to these studies are listed below:

Ammerschlager H, Klein P, Weiser M, Oberbaum M (2005). Behandlung von Entzündungen im Bereich der oberen Atemwege – Vergleich eines homöopathischen Komplexpräparates mit Xylometazolin [Treatment of inflammatory diseases of the upper respiratory tract – comparison of a homeopathic complex remedy with xylometazoline]. Forschende Komplementärmedizin und Klassische Naturheilkunde; 12: 24–31.

Derasse M, Klein P, Weiser M (2005). The effects of a complex homeopathic medicine compared with acetaminophen in the symptomatic treatment of acute febrile infections in children: an observational study. Explore (NY); 1: 33–39.

Friese K-H, Kruse S, Lüdtke R, Moeller H (1997). The homoeopathic treatment of otitis media in children – comparisons with conventional therapy. International Journal of Clinical Pharmacology and Therapeutics; 35: 296–301.

Goossens M, Laekeman G, Aertgeerts B, Buntinx F (2009). Evaluation of the quality of life after individualized homeopathic treatment for seasonal allergic rhinitis. A prospective, open, non-comparative study. Homeopathy; 98: 11–16.

Haidvogl M, Riley DS, Heger M, et al (2007). Homeopathic and conventional treatment for acute respiratory and ear complaints: a comparative study on outcome in the primary care setting. BMC Complementary and Alternative Medicine; 7: 7.

Hubner R, van Haselen R, Klein P (2009). Effectiveness of the homeopathic preparation Neurexan compared with that of commonly used valerian-based preparations for the treatment of nervousness/restlessness – an observational study. Scientific World Journal; 9: 733–745.

Klopp R, Niemer W, Weiser M (2005). Microcirculatory effects of a homeopathic preparation in patients with mild vertigo: an intravital microscopic study. Microvascular Research; 69: 10–16.

Müller-Krampe B, Oberbaum M, Dipl-Math PK, Weiser M (2007). Effects of Spascupreel versus hyoscine butylbromide for gastrointestinal cramps in children. Pediatrics International; 49: 328–334.

Rabe A, Weiser M, Klein P (2004). Effectiveness and tolerability of a homoeopathic remedy compared with conventional therapy for mild viral infections. International Journal of Clinical Practice; 58: 827–832.

Schmiedel V, Klein P (2006). A complex homeopathic preparation for the symptomatic treatment of upper respiratory infections associated with the common cold: An observational study. Explore (NY); 2: 109–114.

Schneider C, Klein P, Stolt P, Oberbaum M (2005). A homeopathic ointment preparation compared with 1% diclofenac gel for acute symptomatic treatment of tendinopathy. Explore (NY); 1: 446–452.

Schneider C, Schneider B, Hanisch J, van Haselen R (2008). The role of a homoeopathic preparation compared with conventional therapy in the treatment of injuries: an observational cohort study. Complementary Therapies in Medicine; 16: 22–27.

Schröder D, Weiser M, Klein P (2003). Efficacy of a homeopathic Crataegus preparation compared with usual therapy for mild (NYHA II) cardiac insufficiency: results of an observational cohort study. European Journal of Heart Failure; 5: 319–326.

Walach H, Lowes T, Mussbach D, et al (2001). The long term effects of homeopathic treatment of chronic headaches: one year follow-up and single case time series analysis. British Homeopathic Journal; 90: 63–72.

Waldschütz R, Klein P (2009). The homeopathic preparation Neurexan vs. valerian for the treatment of insomnia: an observational study. Scientific World Journal; 8: 411–420.

Witt CM, Lüdtke R, Baur R, Willich SN (2009). Homeopathic treatment of patients with chronic low back pain: a prospective observational study with 2 years’ follow-up. Clinical Journal of Pain; 25: 334–339.

Witt CM, Lüdtke R, Willich SN (2009). Homeopathic treatment of chronic headache (ICD-9: 784.0) – a prospective observational study with 2-year follow-up. Forschende Komplementärmedizin; 16: 227–235.

Witt CM, Lüdtke R, Willich SN (2009). Homeopathic treatment of patients with chronic sinusitis: a prospective observational study with 8 years follow-up. BMC Ear Nose and Throat Disorders; 9: 7.

Witt CM, Lüdtke R, Willich SN (2009). Homeopathic treatment of patients with dysmenorrhea: a prospective observational study with 2 years follow-up. Archives of Gynecology and Obstetrics; 280: 603–611.

Witt CM, Lüdtke R, Willich SN (2010). Homeopathic treatment of patients with migraine: a prospective observational study with a 2-year follow-up period. Journal of Alternative and Complementary Medicine; 16: 347–355.

Witt CM, Lüdtke R, Willich SN (2009). Homeopathic treatment of patients with psoriasis – a prospective observational study with 2 years follow-up. Journal of the European Acadamy of Dermatology and Venereology; 23: 538–543.