Taking the antidepressant Prozac increases the risk of infection by a hospital bug, a study has shown.
Scientists found that certain drugs could be the reason for an unexplained link between depression and Clostridium difficile (C.diff) infection.
Most types of antidepressant did not affect infection risk. But a strong association was seen with two out of 12 drugs investigated.
Mirtazapine and fluoxetine –better known as Prozac – both doubled the likelihood of acquiring the bug.
The University of Michigan team found that severely depressed people had a significantly higher risk of C.diff infection than those not suffering from depression. Their chances of being infected were raised by 36%.
Older and widowed patients were also more likely to catch the bug. After finding the link with depression, the researchers went on to look for possible associations with the drugs.
Study leader Dr Mary Rogers said: "Our finding of a link between depression and Clostridium difficile should help us better identify those at risk of infection."