Levonorgestrel (Oral)


Levonorgestrel is a form of emergency contraceptive that is used after failure of another form of birth control or after having unprotected sex. It is effective in stopping the egg from attaching to the wall of the uterus.

Be aware that no form of contraception, including this one, is 100% effective. More effective methods of never having a baby are abstaining from sex or becoming sterile. You should therefore never use Levonorgestrel as a regular birth control method. You can properly discuss all of your birth control options with your doctor.

Plan B One-Step®, the drug name for Levonorgestrel, is available over-the-counter without a prescription. It can be given to any woman who has childbearing potential. However, if you do have questions about this medicine, then you can discuss it in greater depth with a doctor or pharmacist.

Condition(s) treated

  • Unprotected sex

Type of medicine

  • Tablet

Side effects

As well as having its intended effect as an emergency contraceptive, it is possible that you will experience side effects after taking Levonorgestrel. These die effects can range in their severity and their need for medical assistance. Below is a list of the more serious ones. If you experience any of these after taking this medicine, you should contact your doctor immediately.

More common

  • Light or heavy menstrual bleeding

Incidence not known

  • Pain

Below is a list of the less serious side effects that may occur after taking this medicine. If you experience any of the following, then you may find that they simply pass over time as your body adjusts to the medicine. For this reason, they are not necessarily a cause for concern. However, if you do experience any of the following and find them lingering or bothersome, then you can still contact your doctor. They may be able to advise on ways to reduce the unwanted effects.

More common

  • Tenderness of the breasts

Less common

You may experience other side effects that are not listed here. If that is the case, then you can discuss these with your doctor.


Below you can find the typical dose of Levonorgestrel that is given to patients looking to avoid pregnancy. Be aware that your pharmacist or doctor may give you a slightly different prescription or offer different guidance to what is listed below. This is because there may be something unique about your circumstances that require this to be different. Either way, you should take this medicine exactly as prescribed to you. Never take any more and do not take it more frequently. You should only take more of this if told to do so by your doctor.

  • Adults and teenagers. Take one tablet as soon as possible after having unprotected sex or having another contraceptive fail. This should be taken no later than 72 hours after sexual intercourse.

Never take any more of this medicine than what your doctor or pharmacist has told you. You should follow their instructions carefully. Alternatively, follow the instructions on the packaging as closely as you can. Be aware that Levonorgestrel is only designed for occasional use and is not a regular contraceptive method. You can use Levonorgestrel at any point during your monthly period.

With this medicine, you will find a patient information leaflet. You should read this carefully before taking the medicine. If you have any questions after reading this, then they should be addressed to your pharmacist or doctor.

Any woman of childbearing potential can receive the Plan B One-Step® tablets over the counter.

If, within 2 hours of taking this medicine, you vomit, you should tell your doctor. They may require you to take another tablet.


Drug interactions can occur with the consumption of this drug. This may produce unwanted side effects or reduce the effective nature of the drug in treatment. To reduce the risk of these interactions occurring you should give your doctor a full list of all the medications you are currently taking. This should include all over the counter medications (prescription and nonprescription drugs), vitamin supplements and herbal products. Also, make your health care team aware of any other medical conditions you suffer from as these to could increase your risk of interactions. Your doctor will avoid treating you with this drug when possible, but in some cases, it may still be the best treatment plan for you.

The use of this medication alongside any of the following medications is not typically recommended. Your doctor may avoid treating you with this drug altogether or change some of the other medications you are taking.

  • Tranexamic Acid

The use of this medication alongside any of the following medications is not typically recommended but in some cases, it may be required. If you are given both medications at the same time, your doctor may change the dose or frequency in which you use either drug.

  • Ulipristal

The use of this medication alongside any of the following medications can increase your risk of some side effects, however, both drugs may be the best treatment plan for you. If you are given both drugs at the same time, your doctor may change your dose or the frequency in which you use either medication.

  • Rifabutin
  • Fosamprenavir

Let your doctor know if you are taking any of the following drugs:

  • Fluconazole

Other Interactions

Some medications cannot be used with the consumption of food or certain types of food since interactions can occur. The use of tobacco or alcohol may increase your risk of interactions. You should discuss with your doctor about the use of tobacco and alcohol alongside this medication.

The use of this medication alongside any of the following may cause an increased risk of some side effects, however, in some cases, it may be unavoidable. If you use these substances together, your doctor may change your dose or how often you take the medication.

  • Caffeine


Before you take this medicine, your doctor may require you to have a full examination to ensure it is the best treatment for you. You should answer any questions they have as accurately as possible if this is the case. As a part of this, they may need to know about any allergies you suffer from. This can include allergies to animals, dyes, or preservatives. If you have received this over-the-counter, then you should read the packaging carefully to ensure there are no allergy risks that apply to you.

The studies that have taken place to date have not highlighted any pediatric-specific problems that would make this medicine any less useful in teenage female patients. However, it is not recommended that teenage females take this if they have not yet started menstruating.

As of writing, no suitable studies have been performed on elderly patients using this medicine. As such, it is not indicated for use by elderly women.

If you are pregnant, then it is strongly advised that you do not take this medicine. It has highlighted fetal abnormalities as a risk to the unborn child.

As of writing, there are no suitable studies that have been performed on the effects of breastfeeding women using this medicine. If you wish to take the medicine whilst pregnant, then you should first discuss this with your doctor. They can advise you of any increased risks and you can weigh them against the benefits of proceeding.

It's extremely important that your doctor monitors your progress at appointments whilst you are taking this medication. This is to ensure it is working correctly and to test for unwanted side effects.

Even though you are using this medication to prevent falling pregnant, you should know that the use of this medication while pregnant could cause harm to the unborn child. Your doctor may give you a pregnancy test before you use this medication to ensure you are not pregnant. If you think you have become pregnant whilst using the medication, you should tell a healthcare professional immediately.

Call your doctor immediately if you have severe stomach pain or lower abdominal three to five weeks after taking this medication. You have an increased risk of pregnancy outside the womb, known as an ectopic pregnancy. These can be serious and life-threatening. They can also cause issues that may make it more difficult for you to become fall pregnant in the future.

A few days after taking this medication, you may experience some blood spotting. If the bleeding continues for more than one week, check with your doctor immediately.

This medication can make your period for the next month later than expected by a couple of days. After taking this medication, if your next period is more than one week late, you should check with your doctor immediately for a pregnancy test.

This medication will not protect you from getting AIDS/HIV or other sexually transmitted infections. You should talk with your doctor if this is a concern for you.

Your regular birth control method such as the patch or birth control pills may not be as effective whilst you are using this medication. After using this medication, you must use two different forms of birth control. Use the patch or birth control pills together with another form of birth control, such as a diaphragm, condom, or contraceptive jelly or foam, during any other times that you have sex in the same monthly period you used this medication.


You should store this medicine in a sealed container and keep it at room temperature. DO not expose it to moisture, heat, or direct light. Also, never allow it to freeze. It should be kept safely away from children and once treatment is finished, you should dispose of any remaining medicine. Similarly, if any of this medicine goes out-of-date at all, then it should be disposed of. Your doctor or pharmacist can advise on a safe and sensible way to do this.


When used as directed, this drug is successful as an emergency contraceptive. Due to a large number of interactions possible with this drug, it's important that your healthcare team is aware of all possible medications you are taking. You may be required to "prove" you are not pregnant before taking this pill, as to do so could harm an unborn child. This medication is not indicated for use in elderly patients and it is not recommended for use before the start of menstruation in teenage girls. This drug is for occasional emergency use only and it should not replace your normal form of contraceptive. You can take this pill at any time during the month. If you require any further information about the practical uses of this medication or you have any other questions, you should contact your local healthcare professional or doctor for more advice.