What to expect from Plan B®

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When did you have sex

without a contraceptive or have a contraceptive accident?

Please select a time earlier than the present.

You have hours remaining to take Plan B®.

The sooner you take Plan B®, the better it works. Plan B® can help prevent pregnancy if taken within 72 hours, and preferably within 12 hours, after a contraceptive accident or unprotected sex.

It has been more than 72 hours since you had unprotected sex or a contraceptive accident. Please contact a healthcare professional for advice.

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Plan B® is effective

Although few women experience vomiting with Plan B®, if you vomit within two hours of taking Plan B®, you might not have absorbed the medication contained in the pill. Call your healthcare professional, as you might need another dose.

After you’ve taken Plan B®, you should get your next period at the expected time, or a few days early or late. You may experience spotting a few days after taking Plan B®, but this is not your period.

If you’ve taken Plan B® because of missed birth control pills, start your birth control pills right away.

95% effective when treatment is taken within 24 hours of unprotected sex.
If your period is more than a week late, or you haven’t had a period within three weeks of taking Plan B®, it is possible that you’re pregnant. Talk to your doctor.
Good to know: Tell your doctor if you have taken Plan B® within three days of a Pap test, as it may affect your results.

For any questions, you can call the Plan B® medical information line at 1‑888‑919‑0782 (Canadian residents only).

When it should not be used:

Do not use Plan B if:

  • You have a confirmed or suspected pregnancy
  • You are allergic to levonorgestrel or to any ingredients in the formulation (see non-medicinal ingredients below)
  • You have abnormal vaginal bleeding

Side effects of the morning-after pill

It’s very unlikely that you will have any severe reactions to Plan B®. You may have some temporary side effects that will usually pass within 24 hours.

Most common Plan B® side effects

Like all medications, Plan B® can cause some side effects:

  • Nausea
  • Abdominal pain
  • Fatigue
  • Headache
  • Dizziness
  • Breast tenderness
  • Vomiting
  • Diarrhea
  • Irregular menstrual bleeding: Some women may experience spotting after taking Plan B®. The majority of women will have their next menstrual period at the expected time or early. When Plan B® is used repeatedly (more than once in a menstrual cycle, or more than occasional once-a-month use), menstrual changes may occur, including a shorter or longer cycle and a heavier or lighter period than normal.

Serious Warnings and Precautions

Plan B® provides no protection against HIV/AIDS and other sexually transmitted diseases (STDs), such as syphilis, gonorrhea, chlamydia, and herpes. If you are worried about whether you may have been infected with HIV/AIDS, or other sexually transmitted diseases, talk to your health professional about your concerns and ask how you can protect yourself in the future.

If your period is delayed more than 1 week, you should contact your doctor and have a pregnancy test done.

Call your doctor immediately if the following symptoms and signs of serious adverse effects occur:

  • Itching and rash
  • Cramping or severe pain in your stomach or belly prior to your next normal period, since this can be a warning sign of tubal (ectopic) pregnancy – a serious medical problem.
  • Uterine hemorrhage
  • Vaginal hemorrhage

For more details, download the abbreviated Plan B® Product Monograph (Part III):

Product Monograph (Part III): Plan B® 1.5 mg