Members of the Merseyside Skeptics Society gathered at Boots branches around the UK and downed whole bottles of tablets.
They say homeopathy is "scientifically absurd" and want the Boots chain to withdraw all treatments from its shelves.
Homeopathy uses very highly diluted substances to trigger the body to heal itself - but the MSS said: "They are diluted so much there is nothing in them."
At 10.23 on Saturday 30th January, Simon took a vial out of his pocket. He examined the instructions on the label: two pills to be taken every two hours for the first six doses. The contents should not be touched by hand, but be administered directly into the mouth. The vial should be kept both out of reach and sight of children. The middle-aged man then knocked back all 84 tablets and swallowed.
As Simon Singh stood in a public square in London, and waited for the effects of his overdose to take hold, hundreds of other despairing men and women around him poured scores of pills and medicines down their throats.
By taking remedies in quantities far beyond the dosages recommended by their manufacturers, Singh ? a television presenter and author of several books on science ? joined campaigners attempting to demonstrate the case against homoeopathy, and those who supply it.