There is no strong evidence that several herbal remedies commonly taken to relieve troublesome symptoms of the menopause actually work, it has been claimed.

According to an article in the Drugs and Therapeutics Bulletin (DTB), a publication of the British Medical Journal, up to 70% of women in industrialised countries will experience menopausal symptoms, such as hot flushes and night sweats.

On average, such symptoms last for around four years, but in around one in 10 cases, they can last for 12 years or more.

Herbal remedies commonly used to relieve menopausal symptoms include black cohosh, red clover, dong quai, evening primrose oil and ginseng. Others include wild yam extract, chaste tree, hops, sage leaf and kava kava.

However the DTB pointed out that there is little good quality evidence on the effectiveness of herbal remedies, or how they might react with prescription medicines.

“In general, safety has been under researched, which is a major concern given that herbal remedies are often assumed to be ‘safe’ just on the grounds that they are natural,” it said.

It noted that published studies are often poorly designed, include too few participants or do not last long enough to be of real value. Furthermore, the chemical make-up of various preparations of the same herb may differ, which can make it difficult to compare trial results.

There is ‘no convincing evidence’ that red clover extract is effective and little evidence one way or another for dong quai, evening primrose oil, wild yam, chaste tree, hops or sage, the DTB added.