ZocdocAnswersDoes Zithromax make birth control ineffective?

Question

Does Zithromax make birth control ineffective?

My girlfriend and I had sex on the 26th even though she took her last antibiotic pill "Zithromax" on the 25th and we're wondering how likely it is she gets pregnant if I didn't use a condom BUT I did pull out before finishing

Answer

There are some antibiotics that can interact with birth control pills. However, azithromycin is not one that is known to do that. Still, it is best to discuss this with your primary care physician. In fact there are very few antibiotics that do interact with birth control but given that some do the reputation of all of them is that you will get pregnant if you're on antibiotics. This is simply not true. Some antibiotics most specifically rifampin can accelerate the metabolism of the hormones in the birth control. This essentially renders them ineffective because they are being eliminated from the body. However, since there is some theoretical interaction with some antibiotics the labels of many of these medications do come with a warning of using an extra layer of birth control while taking the medication. I would suggest that you schedule an appointment with your primary care physician. This is the kind of doctor that can provide you with this type of advice anytime your place in the new medication. In addition, you can discuss whether or not an extra form of birth control is ever needed in any situation. Remember that it is always a good idea to use condoms whether or not you are protected with birth control pills. This is because condoms can help protect you from STDs.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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