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Levonorgestrel

Pronunciation

Generic Name: levonorgestrel (LEE-voe-nor-JES-trel)
Brand Name: Plan B

Levonorgestrel is used for:

Preventing pregnancy after unprotected sexual intercourse or suspected birth control failure.

Levonorgestrel is a progestin. Exactly how it works is not known. It may prevent pregnancy by inhibiting ovulation, altering transport of sperm or eggs to prevent fertilization, or altering the lining of the uterus to prevent implantation should fertilization occur.

Do NOT use Levonorgestrel if:

  • you are allergic to any ingredient in Levonorgestrel
  • you are or suspect that you are pregnant
  • you have abnormal vaginal bleeding
  • you are taking nevirapine, rifampin, or St. John's wort
  • you have had a stroke or history of bleeding of the brain, known or suspected breast cancer, or a blood clotting disorder

Contact your doctor or health care provider right away if any of these apply to you.

Before using Levonorgestrel:

Some medical conditions may interact with Levonorgestrel. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are planning to become pregnant or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have a history of ectopic pregnancy or you are premenstrual
  • if you have diabetes

Some MEDICINES MAY INTERACT with Levonorgestrel. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Antifungals (eg, ketoconazole), aprepitant, barbiturates (eg, phenobarbital), bosentan, carbamazepine, felbamate, griseofulvin, HIV protease inhibitors (eg, indinavir), hydantoins (eg, phenytoin), modafinil, nevirapine, oxcarbazepine, penicillins (eg, amoxicillin), rifampin, rufinamide, St. John's wort, tetracyclines (eg, doxycycline), topiramate, or troglitazone because they may decrease Levonorgestrel's effectiveness
  • Anticoagulants (eg, warfarin) because their actions and the risk of their side effects may be increased or decreased by Levonorgestrel
  • Beta-adrenergic blockers (eg, metoprolol), corticosteroids (eg, prednisone), selegiline, theophylline, or troleandomycin because their actions and the risk of their side effects may be increased by Levonorgestrel
  • Lamotrigine because its effectiveness is decreased, and when levonorgestrel is stopped, toxic effects, such as nausea, dizziness, and vision problems may occur
  • Valproic acid because its effectiveness may be decreased by Levonorgestrel.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Levonorgestrel may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Levonorgestrel:

Use Levonorgestrel as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • An extra patient leaflet is available with Levonorgestrel. Talk to your pharmacist if you have questions about this information.
  • Take Levonorgestrel as soon as possible after suspected birth control failure or after you have unprotected sexual intercourse. The first dose must be taken within 72 hours. Take the second tablet 12 hours after the first tablet. However, your doctor may instruct you to take Levonorgestrel in a different way. Follow the directions provided by your doctor.
  • Levonorgestrel can be used any time during the menstrual cycle.
  • If vomiting occurs within 1 hour after taking either tablet of Levonorgestrel, talk with your health care provider to discuss whether to repeat that dose.
  • A physical exam is not needed before taking Levonorgestrel. If you are unsure about your general health or pregnancy status, a follow-up physical or pelvic exam may be needed after taking Levonorgestrel.
  • If you miss a dose of Levonorgestrel, contact your doctor right away.

Ask your health care provider any questions you may have about how to use Levonorgestrel.

Important safety information:

  • Levonorgestrel may cause dizziness. This effect may be worse if you take it with alcohol or certain medicines. Use Levonorgestrel with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Levonorgestrel is an emergency contraceptive. It should not be used for routine birth control. If you have sexual intercourse after you take Levonorgestrel but before you have your next menstrual period, be sure to use an effective form of contraception, such as a diaphragm or condom.
  • Levonorgestrel does not protect against HIV infection and other sexually transmitted diseases.
  • Diabetes patients - Levonorgestrel may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
  • Levonorgestrel should not be used in CHILDREN; safety and effectiveness in children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Levonorgestrel will not end an existing pregnancy. Do not use Levonorgestrel if you are pregnant. Levonorgestrel is found in breast milk. If you are or will be breast-feeding while you use Levonorgestrel, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of Levonorgestrel:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Breast tenderness; changes in menstrual flow; diarrhea; dizziness; headache; nausea; stomach pain; tiredness; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); lower stomach pain; missed menstrual period; spotting instead of your usual period.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

See also: Side effects (in more detail)

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center (http://www.aapcc.org), or emergency room immediately. Symptoms may include nausea; vaginal bleeding; vomiting.

Proper storage of Levonorgestrel:

Store Levonorgestrel between 68 and 77 degrees F (20 and 25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep Levonorgestrel out of the reach of children and away from pets.

General information:

  • If you have any questions about Levonorgestrel, please talk with your doctor, pharmacist, or other health care provider.
  • Levonorgestrel is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Levonorgestrel or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Levonorgestrel. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Levonorgestrel. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Levonorgestrel.

Review Date: February 1, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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