Taking ibuprofen could heighten the risk of infertility among young men, a study has found.
Scientists studying the impact of the painkiller on male hormone levels found an 18 per cent drop in testosterone levels among men using the drug for 14 days and a 23 per cent drop after 44 days.
Researchers at the University of Copenhagen, Denmark, said some young men taking ibuprofen developed "compensated hypogonadism", a condition associated with reproductive disorders.
Taking the drug for an extended period of time could lead to erectile dysfunction and fatigue, the Guardian reported.
Writing in the Proceedings of the National Academy of Science journal, David Mobjerg Kristensen warned athletes using ibuprofen to cope with physical strain to be wary of the long-term effects.
Speaking about the study, Richard Quinton, a senior lecturer at Newcastle University, told The Times: "Most warnings...have focused on limiting long-term use in the elderly to prevent gastrointestinal, renal and cardiac adverse effects.
"This study should give pause for thought to sportsmen using them routinely for aches and pains."
The study is the first to suggest that ibuprofen has a negative impact on the testicular health of adult men.
Experts say men should only use ibuprofen long-term when it has been prescribed by their doctor.
