Plan B tablets contain the medicine levonorgestrel, a female hormone that prevents ovulation (the release of an egg from an ovary). This medication also causes changes in your cervical mucus and uterine lining, making it harder for sperm to reach the uterus and harder for a fertilized egg to attach to the uterus.
Plan B is used to prevent pregnancy after unprotected sex or failure of other forms of birth control (such as condom breakage, or missing 2 or more birth control pills).
Plan B may also be used for other purposes not listed in this medication guide.
Important information
Do not use Plan B if you are already pregnant. Plan B will not terminate a pregnancy that has already begun (the fertilized egg has attached to the uterus).
Plan B is not intended for use as a routine form of birth control and should not be used in this manner. Talk with your doctor about the many forms of birth control available.
Do not give this medication to anyone younger than 17 years old. Contact a doctor for medical advice.
Before taking this medicine
Plan B is not intended for use as a routine form of birth control and should not be used in this manner. Talk with your doctor about the many forms of birth control available.
Do not use Plan B if you are already pregnant. Plan B will not terminate a pregnancy that has already begun (the fertilized egg has attached to the uterus).
Before using this medication, tell your doctor if you are allergic to any drugs, or if you have diabetes. You may not be able to use Plan B, or you may need special tests during treatment.
Levonorgestrel can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
Do not give Plan B to anyone younger than 17 years old. Contact a doctor for medical advice.
How should I take Plan B?
Use Plan B exactly as directed on the label, or as it has been prescribed by your doctor. Do not use the medication in larger amounts or for longer than recommended.
The first dose of Plan B must be taken as soon as possible after unprotected sex (no later than 72 hours afterward). The second dose must be taken 12 hours after the first dose. The timing of these doses is very important for this medication to be effective.
Call your doctor right away if you vomit within 1 hour after taking either dose of Plan B. Do not take another dose until you talk with your doctor.
You should be examined by your doctor within 3 weeks after taking Plan B. The doctor will need to confirm that you are not pregnant and that this medication has not caused any harmful effects.
If your period is late by 1 week or longer after the expected date, you may be pregnant. Get a pregnancy test and contact your doctor if you are pregnant. Plan B will not terminate a pregnancy that has already begun (the fertilized egg has attached to the uterus).
Store Plan B at room temperature away from moisture and heat.
What happens if I miss a dose?
Missing a dose of this medication increases your risk of being pregnant.
Contact your doctor if you miss a dose of Plan B. The timing of these doses is very important for this medication to be effective.
What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this medicine.
Overdose symptoms may include nausea and vomiting.
What should I avoid?
Plan B will not protect you from sexually transmitted diseases--including HIV and AIDS. Using a condom is the only way to protect yourself from these diseases. Avoid having unprotected sex.
Plan B side effects
Get emergency medical help if you have any of these signs of an allergic reaction to Plan B: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have severe pain in your lower stomach or side. This could be a sign of a tubal pregnancy (a pregnancy that implants in the fallopian tube instead of the uterus). A tubal pregnancy is a medical emergency.
Less serious Plan B side effects may include:
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nausea, diarrhea, or stomach pain;
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dizziness, tired feeling;
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breast pain or tenderness;
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changes in your menstrual periods; or
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headache.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
What other drugs will affect Plan B?
Before using this medication, tell your doctor if you are using any of the following drugs:
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rifampin (Rifadin, Rifater, Rifamate, Rimactane);
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a barbiturate such as amobarbital (Amytal), butabarbital (Butisol), mephobarbital (Mebaral), secobarbital (Seconal), or phenobarbital (Luminal, Solfoton); or
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seizure medicines such as phenytoin (Dilantin), or carbamazepine (Tegretol).
This list is not complete and there may be other drugs that can affect Plan B. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.
See also
