Hope for embarrassed men - and their unsatisfied partners - affected by one of the commonest sexual problems has been raised by research showing premature ejaculation can be treated safely and effectively with a new drug.
The drug, dapoxetine, more than trebled the time men on the highest dose took to ejaculate, as well as improving their sexual satisfaction and that of their partners.
It was effective even for those who suffered the worst symptoms, ejaculating within seconds of penetration, say the American researchers who publish their findings in the Lancet.
Premature ejaculation affects between a fifth and a third of men and can lead to withdrawal from sex - of either partner - and the breakdown of relationships.
The condition is widely under-treated but increasing numbers of men have been obtaining antidepressants which are known to work even though they are not licensed for the condition.
Men taking antidepressants often report a pleasing side-effect of their treatment is a capacity to "last" longer - with beneficial effects on their sexual relationships. However, the drugs can cause problems such as skin reactions, weight gain and loss of libido.
The new drug, dapoxetine, belongs to the class used in the treatment of depression but has been specifically developed as a treatment for premature ejaculation.
The study, by researchers from the University of Minnesota, involved 2600 men and their partners who were given either a placebo or a low or high dose of dapoxetine.
At the start of the 12-week study, the men ejaculated on average less than a minute after penetration. By the end, those taking the lower 30mg dose were lasting 2.78 minutes on average while those on the higher 60mg dose were lasting 3.32 minutes.
Jon Pryor, who led the study, said: "Dapoxetine improved patients' perceptions of control over ejaculation, satisfaction with sexual intercourse, and overall impression of change in condition. Partners benefited through improved satisfaction with sexual intercourse."
Alan Riley, professor of sexual medicine at the University of Central Lancashire, warned that men should be assessed before being given the drug because the condition could indicate other problems in the relationship.
Asked if delaying ejaculation by two or three minutes was sufficient to make a difference, Professor Riley said: "If a man is ejaculating in less than a minute and he can go to three minutes, that is a significant clinical improvement. Men tend to exaggerate their sexual performance."