The Biological Evidence

Abstract Homeopathy was born as an experimental discipline, as can be seen from the enormous amount of clinical data collected over more than two centuries. However, the medical tradition of homeopathy has been separated from that of conventional science for a long time. Today, an osmotic process between disciplines, previously seen as in conflict, is facilitated because over the last few decades homeopathy has started to use the methods of current medical science and a substantial number of studies - at molecular, cellular and clinical levels – are available. An experimental approach may help to test under controlled conditions the main principles of homeopathy such as “similarity” of drug action and the mechanisms of action of diluted/succussed (“dynamized”) drug solutions. A search of the scientific literature and the experiments carried out by the authors of this review show that there are a number of cellular and animal models where the effect of homeopathic dilutions and the principles of homeopathic medicine have been tested. “In vitro” studies carried out on basophils, lymphocytes, granulocytes and fibroblasts are reviewed. The most consistent body of evidence concerned some fifteen scientific papers, published by independent laboratories, describing a statistically significant effect of ultra-high dilutions of histamine on human basophils. In experimental animals, most results relate to the immunostimulation by ultra-low doses of antigens, the regulation of acute or chronic inflammatory processes, and the behavioral changes (decrease of anxiety-like symptoms) induced by homeopathic treatment. The models utilized by different research groups are heterogeneous and differ as the test medicines, the dilutions and the outcomes are concerned. The evidence emerging from animal models is supporting the traditional “simile” rule, according to which ultra-low doses of compounds, that in high doses are pathogenic, may have paradoxically a protective or curative effect.