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"Could Monistat interfere with Plan B, and how can I tell if Plan B is working?"

ZocdocAnswersCould Monistat interfere with Plan B, and how can I tell if Plan B is working?


Here is my situation: I started my period around the 13th of November. I woke up yesterday morning with itching and discomfort in my vagina and so I figured that it was a yeast infection of some sort and bought the Monistat 1- day package (with the insertable ovule, wipes & cream) and I used Vagisil. This was all around 1pm. Then, later on that night (please don't judge me for this but I drank for the first time and two glasses of wine did it for me & my boyfriend wasn't too sober either.) Anyways, my boyfriend & I had sex and he wore a condom but it broke and I am not on any birth control as of right now, I was supposed to pick it up next week. I took Plan B one dose about thirty minutes later. I'm worried sleepless over this and I would love to know your opinion on how this may turn out. Also, how do I know if plan B is in fact working and whether or not the Monistat capsule could interfere with it. Again, thank you so much.


The good news is that Monistat and Vagisil are both locally administered medications that work inside the vagina but that are minimally absorbed into the body itself. Plan B, on the other hand, is an oral medication which passes into the bloodstream. As such, Monistat and Vagisil, as you have used them, should have no real effects on the effectiveness of the Plan B. That being said, you should know that Plan B, which a great option for preventing pregnancy after unprotected sex, is not perfect. It is only about 80-90% effective at preventing pregnancy, which means that there is still always a small chance you could still be pregnant after taking Plan B. This is why it is recommended that you perform a pregnancy test if you haven't gotten your period within 3 weeks after taking the plan B. It would also be a good idea to talk with your primary care doctor or your OB GYN doctor. They will, first, be able to make sure that this yeast infection is clearing up properly. Also, they will be able to discuss with you other forms of contraception (other than condoms) which could be for effective for you and prevent this worrying situation in the future.

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