There is little evidence to suggest that tailored herbal medicine treatments work, a new study claims.
Research promoting the effectiveness of herbal medicines has been steadily increasing over the past 20 years, the report in the Postgraduate Medical Journal says.
But most of this has involved standard preparations or single herbal extracts, rather than the individually-tailored treatments favoured by some practitioners.
This suggests that they have been sponsored by manufacturers, eager to cash in on the growing market for over-the-counter remedies, the authors claim.
They assessed more than 1,300 studies on herbal treatments for osteoarthritis, irritable bowel syndrome, and cancer drug side-effects, but found only three were of a good enough quality for the results to be reliable.
"There is no convincing evidence that (individualised herbal medicine) is effective in any indication," the authors concluded.
But there is a high risk of side-effects and the potential for herbs to react badly with prescription medicines, they added.
However, in an accompanying editorial, Professor Edzard Ernst, of the Peninsula Medical School at the University of Exeter, warns that the public may soon believe that all herbal medicines are the same.
"Without these distinctions, we will fail to advance our knowledge of the potential benefits of herbal treatments. More importantly, we will also fail in our foremost duty - to protect the public from treatments that cause them harm," he concludes.
"Echinacea made my asthma bad within an hour of taking the medication. It made me wheeze" - Grainne Costello, Potters Bar
"I use echinacea at the first sign of a cold. It often disappears after just a few hours or at the most a couple of days. My husband doesn't take it unless I am here to nag him and his colds last much longer" - Diane, Worcestershire