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Plan B Emergency Contraception 1 Tablet


What is it?

Plan B is one type of emergency contraceptive pill presently approved by Health Canada. It is a back up contraceptive that can be used to prevent pregnancy within 120 hours (approximately 5 days) of a known or suspected contraceptive failure or unprotected sex. Possible reasons for use are:

  • When no contraceptive has been used
  • When a contraceptive method may have failed, including:
    • Condom slippage or breakage
    • Expelled intrauterine device (IUD)
    • Missed or late hormonal contraceptive (e.g. pill, patch, or ring)
    • Over 2 weeks late for contraceptive injection (e.g. Depo-Provera)
    • Partner ejaculates on external genitalia or does not withdraw before ejaculatio (note: withdrawal is not a recommended method of birth control)
    • Fertile period is miscalculated (e.g. using natural family planning method)
  • Cases of sexual assault

How does it work?

Plan B contains the hormone progestin which prevents pregnancy in 3 possible ways:

  • Stops the egg from being released from the ovary
  • Stops fertilization (sperm and egg uniting)
  • Stops the fertilized egg from implanting on the uterine wall

Plan B will not work if you are already pregnant. Although Plan B is not recommended as a regular form of birth control, repeat use poses no health risks.

How to take it:

  • Plan B is the most effective in the first 24 hours after unprotected sexual intercourse but may be taken up to 120 hours after intercourse. The sooner it is taken, the more effective it is.
  • It can be taken at any time during the monthly cycle if there is a concern about becoming pregnant, and most often does not affect your period.
  • The pill should be taken with food.
  • If you vomit in the first two hours after taking Plan B, consult your health care provider and another dose may be recommended.
  • Contraindications to Plan B include allergies to any ingredient in the medication, pregnancy, and any undiagnosed abnormal vaginal bleeding. If there is any suspicion of pregnancy, a pregnancy test should be performed prior to taking Plan B. Plan B will not harm an existing pregnancy.

What happens after I take it?

Side effects of taking Plan B are generally mild and can include:

  • Headache
  • Nausea
  • Vomiting
  • Fatigue
  • Abdominal pain
  • Occasional spotting for 1-3 days

If side effects are severe or you are having an allergic reaction (e.g. itching all over your body, cramping, or severe stomach pain) seek medical attention immediately.

Your period should start within 21 days after taking Plan B. If your period is late by more than 1 week, pregnancy testing and follow-up with your health care provider are recommended. Plan B will not prevent pregnancy from future acts of unprotected intercourse, so use birth control until your next period.

What else should I know?

  • Plan B does not protect you from sexually transmitted infections (STIs). Always use condoms.
  • If you are currently on any form of birth control, continue or restart your birth control on the same day as taking Plan B and use condoms as a back-up for 7 days.
  • If you are not using a regular form of birth control, consider starting and talk to your health care provider.
  • There are other options for emergency contraception (i.e., Ella, Copper IUD). talk to your healthcare provider for more information.