Levonorgestrel (generic Levonelle)

Levonorgestrel is a morning after pill that should be taken within 72 hours (3 days) of unprotected sex.

Levonorgestrel is a synthetic hormone and the active ingredient in this form of emergency contraception. It works to prevent pregnancy from two different angles - either by stopping the ovaries from ovulating or by stopping sperm fertilising an egg if it had already been released.

The earlier Levonorgestrel is taken after unprotected sex, the more likely it is to be effective. It should be taken within 72 hours (3 days), but it is thought that if taken within 24 hours it will prevent 95% of pregnancies, 48 hours it will prevent 85% of pregnancies and 58% within 72 hours.

You will need to take another Levonorgestrel if you are sick within three hours of taking the initial tablet.

Once you have taken Levonorgestrel it will not prevent further pregnancies if you have unprotected sex again. Between taking the tablet and your next period you should use condoms or your regular contraception.

The standard Levonorgestrel dose is 1.5 milligrams. But some women might have to take a double dose (3mg Levonorgestrel) . This can be because of your weight (if you’re over 70kg), or if you’re taking certain medications. You can find out more here.  

Like most medication some people may experience side effects when taking Levonorgestrel. The most common side effects of this form of emergency contraception are nausea, stomach pain and headaches.

If after taking Levonorgestrel your period is late and you experience the above symptoms, you should take a pregnancy test.

For full information on side effects and correct use, see the patient information leaflet. If any side effects concern you, contact us via your Patient Record.

It is important that you tell us about any other medications or recreational drugs you are taking, so that Levonorgestrel can be prescribed safely. Levonorgestrel can be taken alongside most medications, but it can also interact with some medications.

If you need to, you can take the morning after pill more than once in a menstrual cycle. Despite this, the morning after pill shouldn’t be used as a regular form of contraception.