doi: 10.1111/joim.12676 Assessing and regulating homeopathic products R. Fears 1 , G. Griffin 2 , D. Larhammar 3 , V. ter Meulen 1 & J. W. M. van der Meer 4 From the 1 European Academies Science Advisory Council, c/o German National Academy of Sciences Leopoldina, Halle (Saale), Germany; 2 Department of Infectious Diseases and Medicine, St George’s University of London, London, UK; 3 Department of Neuroscience, Uppsala University, Uppsala, Sweden; and 4 Radboud University Medical Center, Nijmegen, The Netherlands Introduction Homeopathy is a system of alternative medicine based on ‘like cures like’ whereby a substance that causes a symptom is used to treat the same symptom in illness. A process of serial dilution and shaking (succussion) is alleged to increase potency, and some practitioners claim that home- opathy works by causing the body to heal itself. Many scientists and physicians are very critical of the health claims made for homeopathic products. Nonetheless, recent usage data from social surveys show that in some European countries (e.g. Aus- tria, France and Germany), more than 10% of the population used homeopathy in the previous 12 months. Based on market analysis, it is anticipated that sales worldwide will grow substantially in the next decade. The European Academies Science Advisory Council (EASAC) recently established a working group including the present authors and others (see Acknowledgements) to prepare a statement [1], building on work by many in the scientific and medical communities, to reinforce criticism of the health and scientific claims made for homeopathic products. EASAC is formed by the national science academies of the EU member states to enable them to collaborate as a collective voice of science in giving advice to European policymakers. EASAC initiated this project because of the increasing discussion in some EU member states and within their academies about issues associated with homeopathy, including its use and labelling, within a broader international context of growing interest in similar issues. Here, we discuss some of the consensus conclu- sions and recommendations from this EASAC statement within the international context. Our purposes are to encourage policy makers to take a critical, evidence-based approach to assessing the claims for homeopathy and to support all those who are interested in stimulating better public engagement and improving consumers’ rights in this contentious area. In this Commentary, we focus on the medical claims for homeopathy and the issues associated with demonstrating, verifying and promoting such claims. The EASAC statement also considered scientific claims relating to poten- tial mechanisms of action, for example effects ascribed to long-range, long-term imprinted mem- ory of water, and concluded that all such claims are unfounded, implausible and contrary to the large, established evidence base regarding dose– response relationships and drug–receptor interac- tions. Our starting point was the affirmation of the fundamental importance of basing both appropri- ately informed consumer choice and the prescrip- tion of medicinal products on accurate and clear information. This requires a standardized, knowl- edge-based regulatory framework to include the efficacy, safety and quality of all health products, underpinned by advertising practices that conform to established principles. We decided that our task was not to re-evaluate all the available evidence for and against the medical claims made for homeo- pathic products but rather to draw on the excellent science-based assessments already made by authoritative and objective bodies. Member acade- mies of EASAC have individually advised on these matters, for example recently in detail in Sweden as well as in Hungary and the UK. Clinical efficacy The Australian government’s National Health and Medical Research Council comprehensively reviewed the published evidence for 68 health conditions and concluded that there are no known diseases for which there is reliable evidence that homeopathy is effective [2]. An earlier UK parlia- mentary inquiry [3] concluded that all the evidence from systematic reviews and meta-analyses [4, 5] conclusively demonstrated that homeopathic ª 2017 The Association for the Publication of the Journal of Internal Medicine 1 Commentary