Homoeopaths claim that Hippocrates may have originated homoeopathy around 400 BC, when he prescribed a small dose of mandrake root to treat mania, knowing it produces mania in much larger doses. In the 16th century, the pioneer of pharmacology Paracelsus declared that small doses of “what makes a man ill also cures him. Samuel Hahnemann (1755–1843) gave homoeopathy its name and expanded its principles in the late 18th century. At that time, mainstream medicine used methods like bloodletting and purging, and administered complex mixtures, such as Venice treacle, which was made from 64 substances including opium, myrrh, and viper’s flesh. These treatments often worsened symptoms and sometimes proved fatal. Hahnemann rejected these practices – which had been extolled for centuries – as irrational and inadvisable; instead, he advocated the use of single drugs at lower doses and promoted an immaterial, vitalistic view of how living organisms function, believing that diseases have spiritual, as well as physical causes.

Hahnemann’s

The term “homoeopathy” was coined by Hahnemann and first appeared in print in 1807.

Hahnemann conceived of homoeopathy while translating a medical treatise by the Scottish physician and chemist William Cullen into German. Being skeptical of Cullen’s theory concerning cinchona’s use for curing malaria, Hahnemann ingested some of the bark specifically to investigate what would happen. He experienced fever, shivering and joint pain: symptoms similar to those of malaria itself. From this, Hahnemann came to believe that all effective drugs produce symptoms in healthy individuals similar to those of the diseases that they treat, in accord with the “law of similars” that had been proposed by ancient physicians. An account of the effects of eating cinchona bark noted by Oliver Wendell Holmes, and published in 1861, failed to reproduce the symptoms Hahnemann reported. Hahnemann’s law of similars is a postulate rather than a scientific law.

Subsequent scientific work shows that cinchona cures malaria because it contains quinine, which kills the Plasmodium falciparum parasite that causes the disease; the mechanism of action is unrelated to Hahnemann’s ideas.