Yes, some antibiotics can decrease the effectiveness of your birth control pills. We recommend using a back-up method (like condoms) or abstaining from sex during the time you’re on the antibiotics and for 7 days after the antibiotics.
If you had sex during the time you were on the antibiotics but didn’t use condoms, then Plan B was a good option, and certainly didn’t hurt. However, since you took Plan B, you may experience some irregular spotting or bleeding throughout your current pill pack. Continue to take your birth control pills consistently and correctly, and your body will get back to normal within the next cycle.
6. January 2012
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