I am highly allergic to penicillin. my husband is taking it. can we have sex? if not what is the safe amount of time to wait. i have tried to research how long it resides in semen to no avail. thank you?

Penicillin can be secreted in semen and can penetrate vaginal tissue and enter your blood stream. It is stated that after the last dose, penicillin will leave the body within 7.7 hours. However it could be longer in different people. I'd wait several days if I were you. For extra protection, if no condom is used, take an antihistamine a couple of hours before intercourse.

You need to avoid sex with your husband since penicillin can concentrate in semen and be passed via vagina. Penicillins can last in the system for at least a few days so I would recommend no sex until a week after he takes the last pill, just to be safe since you say “highly allergic”. Best of luck to you!