Levonorgestrel prevents pregnancy after birth control failure (such as a broken condom) or unprotected sex by preventing the release of an egg (ovulation) during your menstrual cycle. It also makes vaginal fluid thicker to help prevent sperm from reaching an egg (fertilization) and changes the lining of the uterus (womb) to prevent attachment of a fertilized egg.
This medication will not stop an existing pregnancy or protect you or your partner against sexually transmitted diseases (such as HIV, gonorrhea, chlamydia).
This medication may not work well in women over a certain weight (for example, greater than 164 pounds or 74 kilograms).
How to use levonorgestrel
If you are taking the over-the-counter product to self-treat, read all directions on the product package before taking this medication. If you have any questions, consult your pharmacist. If your doctor has prescribed this medication, take it as directed.
Take this medication by mouth as soon as possible after unprotected sex. Your instructions for use depend on the brand you take. Therefore, check the label on your brand and ask your doctor or pharmacist if you have any questions. Take as directed, usually 2 tablets at once; or take 1 tablet and then take the second tablet 12 hours after the first tablet. This medication may be taken with or without food. This medication works best when it is taken within 72 hours (3 days) after unprotected sex.
If you vomit within 2 hours of taking a dose of this medication, contact your doctor to ask if you need to repeat the dose.
After you take this medication, the time when your period comes and how much you bleed may change. Tell your doctor right away if your period is more than 7 days late. You may need to take a pregnancy test.
If you think you may have a serious medical problem, get medical help right away.
