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Emergency Contraceptive Pill (Plan B)

What is it?

The emergency contraceptive pill, or “morning after pill”, is used to prevent or reduce the chance of an unplanned pregnancy after unprotected sex. There are different brands of this pill but the brand offered at the health unit is Plan B. Plan B contains a high dose of the hormone progestin (Levonorgestrel).

Examples of unprotected sex:

  • No birth control used (hormonal method or condom)
  • Birth control failure such as missed pills, patch fell off, forgot to replace Nuvaring, late for Depo injection, etc.
  • Condom broke, leaked, slipped off, or not used at all
  • IUD/IUS came out

How to take this medication:

Plan B is a pill that can be taken with water. This medication is most effective if used within 24 hours after unprotected sex, but can be used within 5 days after unprotected sex. Effectiveness of Plan B decreases the longer you wait to take it.

A nurse will take your blood pressure before giving you the medication.

Tell your health care provider if you vomit within 2 hours of taking Plan B. Another dose may be needed.

Do NOT take this medication if you:

Are allergic to Levonorgestrel or had an allergic reaction to Plan B in the past.

Are pregnant or suspect you are pregnant.

Have abnormal bleeding from your vagina.

Have active liver disease.

Have or suspect you have breast cancer.

Tell your health care provider if you:

Have high blood pressure.

Experience headaches or migraines.

Have diabetes.

Are taking any medications (see “Drug Interactions” section below).

Plan B may be less effective in people with a body mass index (BMI) of 25–29 and not likely effective if BMI is 30 or higher. A nurse can help you figure out your BMI.

Side effects:

Contact your health care provider right away if you experience any of the below symptoms:

  • Itching and rash
  • Cramping or severe pain in your stomach or belly before you get your next period (warning sign of ectopic pregnancy)
  • Heavy bleeding from your vagina that isn’t your period

Plan B may cause some side effects. These usually pass within 24 hours of taking Plan B. Common side effects are listed below. If any of the below symptoms last longer than 48 hours or are severe, contact your health care provider.

  • Nausea
  • Abdominal pain
  • Fatigue
  • Headache
  • Dizziness
  • Breast tenderness
  • Vomiting
  • Diarrhea
  • Spotting
  • Migraine or severe headache
  • Lower belly pain
  • Painful menstruation
  • Discharge from vagina

Drug interactions:

The following medications can make Plan B less effective:

  • Anti-HIV drugs
  • Anticonvulsants
  • Antibiotics
  • Rifampicin
  • Rifabutin
  • Griseofulvin
  • St. John’s wort
  • Ulipristal acetate


This medication should be kept at room temperature and in dry conditions. Do not allow medication to freeze. Keep out of reach and sight of children.

Points to remember:

You may experience spotting a few days after taking Plan B. Your next period should come on time but may be a few days early or late. If your period is over 1 week late, talk to your health care provider about a pregnancy test and to discuss your options.

You should use a different form of birth control or not have sex until your period returns. Unprotected sex that happens after taking Plan B can still result in a pregnancy.

Plan B should not be used on a regular basis as a form of birth control.

Taking Plan B within 3 days of having a Pap test may affect your results.

Plan B does not provide protection from sexually transmitted infections.