The tincture is part of the Prince's 'Duchy Herbals' range
Prince Charles has been accused of exploiting the public in times of hardship by launching what a leading scientist calls a "dodgy" detox mix.
Edzard Ernst, the UK's first professor of complementary medicine, said the Duchy Originals detox tincture was based on "outright quackery".
There was no scientific evidence to show that detox products work, he said.
Duchy Originals says the product is a "natural aid to digestion and supports the body's elimination processes".
But Professor Ernst of Peninsula Medical School said Prince Charles and his advisers appeared to be deliberately ignoring science, preferring "to rely on 'make-believe' and superstition".
He added: "Prince Charles thus financially exploits a gullible public in a time of financial hardship."
Marketed as Duchy Herbals' Detox Tincture, the artichoke and dandelion mix is described as "a food supplement to help eliminate toxins and aid digestion".
It costs £10 for a 50ml bottle.
Andrew Baker, the head of Duchy Originals, said the tincture "is not – and has never been described as – a medicine, remedy or cure for any disease.
"There is no "quackery", no "make believe" and no "superstition" in any of the Duchy Originals herbal tinctures. We find it unfortunate that Professor Ernst should chase sensationalist headlines in this way rather than concentrating on accuracy and objectivity."
Professor Ernst said the suggestion that such products remove toxins from the body was "implausible, unproven and dangerous".
"Nothing would, of course, be easier than to demonstrate that detox products work. All one needed to do is to take a few blood samples from volunteers and test whether this or that toxin is eliminated from the body faster than normal," he said.
"But where are the studies that demonstrate efficacy? They do not exist, and the reason is simple: these products have no real detoxification effects."
Earlier this year the charitable trust Sense About Science produced a report seeking to debunk claims made about detox products.
Its researchers reviewed a series of products, from bottled water to face scrub, and found the detox assertions to be overwhelmingly meaningless.
"It seems outrageous for companies to be making money selling meaningless products but for the heir to the throne to be doing so, at £10 a pop, is even more inappropriate," said Tom Wells, who helped carry out the original research.
"We'd like to see an end to detox products on the British high street, starting with Prince Charles' detox tincture."
It is not the first time Professor Ernst has criticised Prince Charles.
His 2008 book Trick or treatment? Alternative Medicine on Trial is dedicated with irony to the prince, who has long been a supporter of complementary medicine - and particularly homeopathy.