In what is being billed as "rationalism's Kool-Aid moment", a mass "overdose" is being planned next week in protest at the marketing of homoeopathic medicines.
More than 300 people who style themselves as "homoeopathy sceptics" will each swallow an entire bottle of homoeopathic pills in protest at the continued marketing of homoeopathic medicines by Boots, the high street chemist chain.
The protest is due to take place at 10.23am on Saturday 30 January. It is organised by the "10.23 Group", who take their name from Avogadro's constant, which they claim proves that homoeopathy cannot work.
Avogadro's constant – roughly 10 to the 23rd power – places an upper limit, broadly speaking, on the number of molecules in a given volume of liquid or gas.
Successive dilutions used in the preparation of homoeopathic remedies reduce the amount of the original ingredient beyond this number, with the result that not a single molecule remains.
This has always been the sticking point for scientists who express bafflement at the notion that a homoeopathic "tincture", which contains not a single molecule of the active ingredient from which it was made, can have any effect.
In response, homoeopaths describe the process of repeatedly diluting and shaking a remedy as "potentisation", in which the influence of the active ingredient is transferred to the tincture. The water thus retains a "memory" of the substance.
In an open letter to Boots last November, the 10.23 Group wrote: "The majority of people do not have the time or inclination to check whether the scientific literature supports the claims of efficacy made by products such as homoeopathy. We trust brands such as Boots to check the facts for us, to provide sound medical advice that is in our interest, and supply only those products with a demonstrable medical benefit. We don't expect to find products on the shelf at our local pharmacy which do not work."
The letter also warned that the products could be dangerous if they led patients to delay seeking proper medical assistance because they believed homoeopathy could treat their condition.
There is a long tradition in science of researchers experimenting on themselves to prove a remedy works. But this will be the first time volunteers have swallowed pills to prove they don't.
If it turns out that there is something in them, then the guinea pigs may get their comeuppance. But they say their "overdose" will demonstrate that "these remedies, prepared according to a long-discredited 18th-century ritual, are nothing but sugar pills."
In England, an estimated 470,000 people use homoeopathic remedies every year. Branches of Boots carry shelves of remedies including arnica, nux vomica, pulsatilla and rhus tox in the "complementary medicine" section. The Queen, David Beckham and Geri Halliwell are among those said to swear by them.
The British Homeopathic Association claims that heightened public awareness of the dangers of chemicals in the food chain, growing resistance to antibiotics through over-use, and concerns about the side effects of conventional drugs, are contributing to a rethink about the way we live and how we seek to regain health.
Boots said in a statement: "We know that many people believe in the benefits of complementary medicines and we aim to offer the products we know our customers want."