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Birth Control Health Center

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Plan B One-Step

How to Take Plan B One-Step continued...

You can take Plan B One-Step if:

  • You didn't use any birth control.
  • The condom came off or broke.
  • The diaphragm slipped out of place.
  • You missed at least two or three active birth control pills in a row.
  • You forgot to insert your ring or apply your patch.
  • Your partner didn't pull out in time.
  • You have another reason to think your birth control might not have worked.
  • You were forced to have sex.

Remember: Plan B One-Step will not protect you from getting pregnant if you have sex after taking the pills. Instead, you need to take it right after you have unprotected sex.

Do not take Plan B One-Step if:

  • You know you are pregnant or suspect you might be.
  • You have a history of allergy or hypersensitivity to its ingredients.
  • You have a history of recent abnormal vaginal bleeding that your doctor has not yet evaluated.
  • You weigh over 165 pounds.

Side Effects of Plan B One-Step

Many women have taken emergency contraception without serious complications. But it's a good idea to ask your doctor about possible interactions with other medications.

Plan B One-Step is considered safe for most women. You should not take it if you are pregnant because it will not end the pregnancy.

Potential side effects of Plan B One-Step include:

If you vomit within two hours after taking the drug, call a healthcare professional to find out if you should repeat the dose.

With Plan B One-Step, you may also have some unexpected bleeding. It should go away by the time of your next period. However, it is possible that Plan B One-Step may cause your next period to be heavier or lighter than usual. It may also come earlier or later than is normal for you. If you don't get your period within three weeks, get a pregnancy test to make sure you're not pregnant.

WebMD Medical Reference

Reviewed by Kecia Gaither, MD, MPH on October 03, 2014
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