The ‘placebo effect’ can be described as a positive change seen after medical treatment which is caused solely by the patient’s psychological response to being given the treatment. In other words, improvement occurs because the patient expects to get better.
Placebo effects are associated with all medical interventions. Placebo-controlled trials – which directly compare an experimental treatment with an inactive ‘dummy’ treatment – have therefore become a routine part of medical research in order to discover whether new treatments have any clinical effects above and beyond placebo.
Placebo effects in conventional medicine
Commentators frequently raise the subject of what role placebo plays in homeopathy, which can give a misleading impression that this issue is unique to homeopathy. In fact placebo has become a burning issue in the pharmaceutical industry in recent years, as an increasing number of initially promising new drugs have had to be abandoned during development because they are found to be no more effective than placebo1.
The level of placebo effect can be surprisingly high and even bring accepted treatments into question. The level of placebo effect can vary too with some placebos being weak and others strong2. The placebo effect is also undergoing a surge in research activity as a distinct phenomenon in its own right – there is much debate over exactly what the ‘placebo effect’ is and how it should be defined, studied and utilised3,4.
Placebo effects in homeopathy
Results from numerous high quality randomised controlled trials (RCTs) and several systematic reviews have shown that homeopathic medicines have a clinical effect above and beyond placebo (see Clinical trials section for more information). Homeopathic treatment will of course include a placebo effect, but this should not be confused with additional indirect effects such as the therapeutic effect of the homeopathic consultation and patient-practitioner relationship.
Treatment by a homeopath gives patients the opportunity to explore their health problems thoroughly during one-to-one consultations with their practitioner. Some sceptics suggest that this process initiates a placebo effect responsible for much of the clinical results seen with homeopathic treatment, but a more accurate description would be that the homeopathic consultation has a ‘therapeutic effect’. If a patient treated by a psychologist improved, this would be correctly described as a therapeutic effect of the treatment not a placebo effect. The homeopathic consultation is clearly different from a psychotherapy consultation, but it does appear to have a strong therapeutic effect of great value to patients which homeopaths are trained to utilise appropriately.
1) Placebos Are Getting More Effective. Drugmakers Are Desperate to Know Why by Steve Silberman, 24 August 2009. www.wired.com
2) Howick J, et al., Are treatments more effective than placebos? A systematic review and meta-analysis. PLoS One, 2013, 8(5); e62599
3) Moerman, D. Meaning, Medicine and the Placebo Effect. Cambridge University Press, 2008
4) Harrington, A (ed). The Placebo Effect: An Interdisciplinary Exploration. Harvard University Press, 2000.