From Greek words: homeo (similar) and pathos (suffering). A medical system based on the use of minute quantities of remedies that in massive doses would produce effects similar to those of the disease being treated. First practiced by German physician Samuel Hahnemann (1755-1843) who was inspired by the theory of 'like cures like'. Homoeopathic medicines are ultramolecular, they are diluted (see: potentized) to such a degree that not even a single molecule of the original solute is likely to be present. As drug actions are conventionally understood in biochemical terms, homoeopathy presents an enormous intellectual challenge, if not a complete impasse. Many scientists have suggested that the clinical effects of homoeopathic medicines are solely due to the placebo effect. However, there have been rigorous, replicated, double blind, randomised trials showing significant differences between homoeopathic and placebo tablets.