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Levonorgestrel Oral tablet [Emergency Contraception]

It prevents pregnancy if taken within the 72 hours after unprotected sex

Generic Name: levonorgestrel  |  Brand Name: Mirena

Brand Names: Norplant System, Mirena, Plan B

What is this medicine?

LEVONORGESTREL (LEE voe nor jes trel) is an emergency contraceptive (birth control pill). It prevents pregnancy if taken within the 72 hours after unprotected sex. This medicine will not work if you are already pregnant.

What should I tell my health care provider before I take this medicine?

They need to know if you have or ever had any of these conditions:
  • blood sugar problems, like diabetes
  • cancer of the breast, cervix, ovary, uterus, vagina, or unusual vaginal bleeding
  • fibroids
  • liver disease
  • menstrual problems
  • migraine headaches
  • an unusual or allergic reaction to levonorgestrel, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth. Your doctor may want you to use a quick-response pregnancy test prior to using the tablets. Take your medicine as soon as you can after having unprotected sex, preferably in the first 24 hours, but no later than 72 hours (3 days) after the event. Follow the dose instructions of your health care provider exactly. Do not take any extra pills. Extra pills will not decrease your risk of pregnancy, but may increase your risk of side effects.

A patient package insert for the product will be given with each prescription and refill. Read this sheet carefully each time. The sheet may change frequently.

Contact your pediatrician regarding the use of this medicine in children. Special care may be needed. This medicine has been used in female children who have started having menstrual periods.

What if I miss a dose?

If you miss a dose or vomit within 1 hour of taking your dose, you MUST contact your health care professional for instructions.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • amprenavir
  • bosentan
  • fosamprenavir

This medicine may also interact with the following medications:

  • aprepitant
  • barbiturate medicines for inducing sleep or treating seizures
  • bexarotene
  • griseofulvin
  • medicines to treat seizures like carbamazepine, ethotoin, felbamate, oxcarbazepine, phenytoin, topiramate
  • modafinil
  • pioglitazone
  • rifabutin
  • rifampin
  • rifapentine
  • some medicines to treat HIV infection like atazanavir, indinavir, lopinavir, nelfinavir, tipranavir, ritonavir
  • St. John's wort
  • warfarin

What should I watch for while using this medicine?

Emergency birth control is not to be used routinely to prevent pregnancy. Discuss birth control options with your health care provider. Make a follow-up appointment to see your health care provider in 3 to 4 weeks after using this medicine.

It is common to have spotting after using this medicine. If you miss your next period, the possibility of pregnancy must be considered. See your health care professional as soon as you can and get a pregnancy test.

Smoking increases the risk of getting a blood clot or having a stroke while you are taking birth control pills, especially if you are more than 35 years old. You are strongly advised not to smoke.

This medicine does not protect you against HIV infection (AIDS) or any other sexually transmitted diseases.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • Severe side effects are not common. However, the potential for severe side effects may exist and you may want to discuss these with your health care provider.

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • abdominal pain or cramping
  • breast tenderness
  • dizziness
  • nausea
  • spotting


Last Updated: December 03, 2009
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