Drug information provided by: Merative, Micromedex®
Levonorgestrel is an emergency contraceptive that is used to prevent pregnancy after unprotected sex or after failure of another birth control method. It works by preventing a woman's egg from fully developing. It may also prevent the attachment of the woman's egg to the wall of the uterus (womb).
No contraceptive method is 100 percent effective. Birth control methods such as having surgery to become sterile or not having sex are more effective. This medicine should not be used as a regular method of birth control. Discuss your options for birth control with your doctor.
Plan B One-Step® is available as an over-the-counter medicine for any woman of childbearing potential.
This product is available in the following dosage forms:
Portions of this document last updated: Sept. 01, 2023
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