How Plan B® works

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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.

It’s called the morning-after pill for a reason

Unlike regular birth control methods, which are used before or during sex, Plan B® is used to prevent pregnancy after unprotected sex or following a contraceptive accident.

Plan B® comes in a one-pill dose (levonorgestrel 1.5 mg). If taken within 72 hours (three days) and preferably within 12 hours of a contraceptive accident or unprotected sex, Plan B® can prevent pregnancy.

Available for all women who need it

Plan B® is the best-selling brand of emergency contraceptive in Canada.* Find it on the shelf at your local pharmacy.

Find a pharmacy

How does Plan B®
prevent pregnancy?

Each Plan B® tablet contains 1.5 mg of levonorgestrel—an ingredient that is also commonly found in birth control pills.

When taken correctly (within 72 hours of a contraceptive accident or unprotected sex), Plan B® works by:

  • Temporarily stopping the release of an egg from the ovary (ovulation)
  • Preventing fertilization
  • Preventing a fertilized egg from attaching to the uterus by changing the uterine lining

Plan B® is not an abortion pill—if you take Plan B®, you will not be terminating a pregnancy.

*IQVIA/IMS Health, CDH, 2019 sales in units.
†Except in Québec (where you will need to speak to the pharmacist).