I always see questions asking how long after taking an antibiotic can you have unprotected sex again. But what If I had unprotected sex last night and was just prescribed an antibiotic that said it may affect the effectiveness of birth control. When is it safe to start taking the antibiotic with no risk of pregnancy?
If you were prescribed an antibiotic, you need to start taking it the day it was prescribed. You’ll just have to push your luck regarding last night’s activity (which you knew might cause a problem) but stop the sex until at least a week after medication is finished.
It seems impossible that anyone old enough to be sexually active is not mature enough to abstain during infections and antibiotic therapy.
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