How the interaction occurs:
When these two medicines are taken together, the penicillin medicine may alter the way your body processes the birth control pill.
What might happen:
The effect of your birth control pills may decrease and cause breakthrough bleeding, spotting, or even unintended pregnancy.
What you should do about this interaction:
General consensus is that a backup method of birth control is not needed while taking this antibiotic. If you have questions or concerns, discuss them with your healthcare professional (e.g. doctor or pharmacist).Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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