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Plan B One-Step is a single tablet you take by mouth. It must be taken as directed within 72 hours (3 days) after unprotected sex or birth control failure to help prevent pregnancy. The sooner you take it, the better it works.

Who should take it?

It’s a backup method of birth control you can use when:

  • You didn’t use any birth control method
  • Your regular birth control method failed (eg, your partner’s condom broke or slipped)
  • You made a mistake with your regular birth control method (eg, you forgot to take your regular birth control pill)

If you have any questions about whether you should take Plan B One-Step, please talk to your healthcare professional.

How long after taking Plan B One-Step should I resume my regular birth control?

You should resume your regular method of birth control right away—or start one, if you don’t have a regular method—since Plan B One-Step does not protect against additional incidents of unprotected sex. For more information, talk to your healthcare professional.

Who should not take it?

Do not take Plan B One-Step:

  • If you’re already pregnant, because it won’t work
  • If you’re allergic to levonorgestrel or any of the ingredients in Plan B One-Step
  • In place of regular birth control, because it’s not as effective
  • If you’re male

How will I know it worked?

You will know Plan B One-Step worked when you get your next period, which should come at the expected time, or within a week of the expected time. If your period is more than a week late, it is possible you may be pregnant. You should get a pregnancy test and follow up with your healthcare professional.

Keep in mind; Plan B One-Step may be less likely to work if:

  • You’ve already had unprotected sex or birth control failure earlier in your menstrual cycle, as you may already be pregnant
  • You have had unprotected sex or birth control failure again in the same menstrual cycle after taking Plan B One-Step, because it only protects against one incident of unprotected sex or birth control failure
  • You vomit within 2 hours of taking Plan B One-Step—talk to a healthcare professional to find out if you should repeat the dose

Plan B One-Step won’t protect you against HIV/AIDS or other sexually transmitted diseases (STDs).

Plan B One-Step is a registered trademark of Foundation Consumer Healthcare.
© 2018 Foundation Consumer Healthcare. This site is intended for US audiences only.