Levonorgestrel emergency contraceptive 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).

Levonorgestrel emergency contraceptive may also be used for purposes not listed in this medication guide.

Levonorgestrel emergency contraceptive is not intended for use as a routine form of birth control. Talk with your doctor about the many forms of birth control available.

Do not use this medicine if you are already pregnant. Levonorgestrel emergency contraceptive will not terminate a pregnancy that has already begun (the fertilized egg has attached to the uterus).

Not approved for use by anyone younger than 17 years old.

You should not use levonorgestrel if you are allergic to it.

Ask a doctor or pharmacist before taking levonorgestrel if you regularly use medication for seizures, tuberculosis, or HIV/AIDS. Certain medications can make levonorgestrel less effective as an emergency form of contraception.

Levonorgestrel may slow breast milk production. Tell your doctor if you are breastfeeding.

Use Plan B One-Step (Oral) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor or seek emergency medical help 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.

Common side effects may include:

• stomach pain;
• breast pain or tenderness;
• nausea, vomiting, diarrhea;
• headache, dizziness;
• feeling tired; or
• changes in your menstrual periods.

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.

Levonorgestrel emergency contraceptive 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.