A pill dubbed the female Viagra gives only "marginal" benefits - and causes tiredness, nausea and dizziness, a study has concluded.
Flibanserin, which is meant to restore flagging libido in women, was launched last year to huge fanfare. But scientists say trials of the drug show it works little better than a placebo.
And they found that one in three women who took the drug experienced side effects including nausea and fatigue. Sold under the brand name Addyi, it was approved by the US Food and Drug Administration last year as a treatment for hypoactive sexual desire disorder - thought to affect 10 to 40 per cent of women - following two previous rejections, and may be sold in Britain in future.
But the report by the Erasmus University Medical Centre in the Netherlands says the risks of taking flibanserin outweigh its minimal benefits. The team reviewed eight trials involving nearly 6,000 women and found that women who took the drug - which works on the brain's pleasure centre - had an average of just one extra satisfying sexual experience every two months compared with women who took a placebo.
They were also about four times more likely to experience dizziness and sleepiness, more than twice as likely to experience nausea and around 60 per cent more likely to experience fatigue.