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A 24-year-old female asked:

I recently finished an antibiotic about a week ago. how long does it stay in your system and how long can it affect my birth control?

1 doctor answer1 doctor weighed in
Dr. Kathleen Mullane
Internal Medicine 33 years experience
Elimination issue: That depends on the antibiotic. Usually we say that it takes 5 half lives of the antibiotic to get out of the body. More importantly, the effect on your normal gut bacteria; can be altered > 1 month depending on how broad spectrum the antibiotic. Flora helps ocp absorption. It would be safest to at least use a secondary mode of protection for a month after you complete your course of antibiotic.
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Created for people with ongoing healthcare needs but benefits everyone.
Last updated Oct 4, 2016

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