Q. I am currently taking amoxicillin for a sinus infection but my wife is allergic to penicillin. Is there any possibility that she would have a bad reaction if we had unprotected sex?
A. There are reports in the medical literature of women reacting to a medicine in their husband’s semen. The concentration is usually very low, but for sensitive people, even a little exposure can be risky. Over 20 years ago we heard from a reader who reported the following reaction:
"I know this sounds bizarre, but I’m convinced I have been reacting to the penicillin my husband has been taking for a strep throat. When I was 10 I had an allergic reaction to penicillin. Last week I experienced hives and wheezing soon after we made love.”
Men may also react to medicines their wives are taking. It would be prudent to use a condom.
