Homeopathy (also spelled homœopathy or homoeopathy) from the Greek words όμοιος, hómoios (similar) and πάθος, páthos (suffering), is a system of alternative medicine, notable for its controversial practice of prescribing water-based solutions that in many cases do not contain chemically active ingredients. The theory of homeopathy was developed by the Saxon physician Samuel Hahnemann (1755–1843) and first published in 1796. It is growing in popularity in some areas where it is practiced today, but neither its empirical nor its theoretical foundation meets minimum scientific standards.
Homeopathy calls for treating "like with like", a doctrine referred to as the law of similars. The practitioner considers the totality of symptoms of a given case, then chooses a remedy that has been reported in a homeopathic proving to produce a similar set of symptoms in healthy subjects. This remedy is usually given in extremely low concentrations prepared according to a procedure known as potentisation, because it is held that this process gives higher dilutions more therapeutic power.