Levonorgestrel is used by women to prevent pregnancy after birth control failure (such as a broken condom) or unprotected sex. This medication is an emergency contraceptive and should not be used as a regular form of birth control. It is a progestin hormone that works mainly 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 may not work well in women over a certain weight (for example, greater than 164 pounds or 74 kilograms). Talk to your doctor for more details and to see if this medication is right for you.
Check the ingredients on the label even if you have used the product before. The manufacturer may have changed the ingredients. Also, products with similar names may contain different ingredients meant for different purposes. Taking the wrong product could harm you.
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.
Nausea/vomiting, abdominal pain, tiredness, dizziness, changes in vaginal bleeding, breast tenderness, diarrhea, or headache may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: severe lower stomach pain (especially 3 to 5 weeks after taking levonorgestrel).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
In the US -
Before taking levonorgestrel, tell your doctor or pharmacist if you are allergic to it; or to other progestins (such as norethindrone); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: unexplained vaginal bleeding.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
This medication must not be used during pregnancy. If you become pregnant or think you may be pregnant, tell your doctor immediately.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Other medications can affect the removal of levonorgestrel from your body, which may affect how levonorgestrel works. Examples include griseofulvin, modafinil, rifamycins (such as rifampin, rifabutin), St. John's wort, drugs used to treat seizures (such as barbiturates, carbamazepine, felbamate, phenytoin, primidone, topiramate), HIV drugs (such as nelfinavir, nevirapine, ritonavir), among others.
Overdose with this medication is very unlikely. However, if overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe nausea/vomiting.
Keep all regular medical and laboratory appointments.
If you miss a dose, contact your doctor right away.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised January 2015. Copyright(c) 2015 First Databank, Inc.
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