- Study finds 75 per cent of products have no warnings
Herbal medicines can pose serious health risks that consumers are not warned about, researchers say.
They surveyed different versions of the five most popular remedies – St John’s wort, Asian ginseng, echinacea, garlic and ginkgo – and found they were commonly sold over the counter with no safety warnings.
Yet St John’s wort, widely used to combat low moods, can reduce the effectiveness of the contraceptive pill.
Risks: St John's wort (left) and Asian ginseng both have hidden dangers
Ginkgo, which is said to improve circulation and alertness, is also a blood-thinner that should not be combined with other medication.
And Asian ginseng, used to boost the immune system, and echinacea, often used to protect against colds, also have their dangers.
Even garlic – used to lower high blood pressure – can be dangerous in large quantities.
The researchers at Leeds University’s school of pharmacy surveyed 68 products on sale to the public and found 51 of them (75 per cent) contained no information on precautions, interactions with other medicines or side effects.Seventy per cent of them (48 of the 68 products) were marketed as food supplements, despite their powerful effects.
Just three products contained sufficient information on risks and side-effects.
The products were bought at two health-food stores, three chain pharmacies and three supermarket chemists.
Under an EU directive in April this year, certain herbal medicines have to be licensed and carry health information, but of these five products, only St John’s wort and echinacea require a licence.
Of the 12 St John’s wort products surveyed by the Leeds researchers, four contained no safety messages, and of 13 echinacea products, nine failed to provide the required information.
The other three remedies do not have to carry any warnings, as long as they make no medical claims.
The fact that so few products provided sufficient information could be because shops are allowed to continue selling old stock, with no warnings, until their expiry date.
Professor Theo Raynor, who led the study, said: ‘The best advice to consumers is “buyer beware”. Herbal medicines . . . should be taken with as much caution as any over-the-counter medicine.
‘Any substance that affects the body has the potential to do harm if not taken correctly.’
He advised consumers to look for the Traditional Herbal Registration (THR) logo, which means remedies have been approved by the Government.
‘People should tell their doctor about herbal medicines they are taking so they receive the best care,’ he added.