Scientists have called into question the efficacy of herbal remedies on menopausal symptoms after a review of randomised clinical trials found only limited evidence that they worked.
UK researchers Dr Alyson Huntley and Dr Edzard Ernst at the universities of Exeter and Plymouth in the UK set out to examine literature references on herbal remedies for menopausal symptoms.
Trials were only considered if the outcome measures related to the physical or psychological impact of the menopause and studies were excluded if menopause was artificially induced.
They identified 18 randomised trials, four involving black cohosh, four red clover, three kava, one each of dong-quai, evening primrose oil and ginseng, and four combination products. According to the scientists, trial quality was generally good.
But the authors concluded that as yet there is no convincing evidence for the efficacy of any herbal medicinal product in the treatment of menopausal symptoms.
Their review, published in Menopause (Vol 10(5), 2003), did find however that black cohosh showed promise, although they report that this was limited by the 'poor methodology of the trials'.
In addition, the red clover trials suggested it could relieve the more severe menopausal symptoms. Turning to the controversial kava kava compound, they found, 'some evidence for the use of kava kava', but safety concerns currently outweigh any possible benefit. But for the remaining herbals involved in the review - dong-quai, evening primrose oil and ginseng - the evidence is 'inconclusive', concluded the researchers.