Levonorgestrel
Is It Right for You?
A complete guide to Levonorgestrel — what it treats, how it works, dosages, side effects, and when a clinician may prescribe it following an online consultation.
What Is Levonorgestrel?
Levonorgestrel is a widely used progestogen. It is found in several contraceptive methods, including combined and progestogen-only pills, the hormonal coil (intrauterine system), and emergency contraception, and is also used in some HRT preparations.
Its form and dose depend on the use - from a small daily tablet, to a single emergency dose, to a device releasing hormone in the womb, to a patch combined with oestrogen for menopause symptoms.
Levonorgestrel products range from pharmacy emergency contraception to prescription-only contraceptives and HRT in the UK. A licensed clinician can review your needs through a telehealth consultation and advise or prescribe where appropriate.
What Conditions Is Levonorgestrel Used For?
Levonorgestrel is used for:
in combined pills, progestogen-only pills, and the hormonal coil.
as a single dose taken after unprotected sex, the sooner the better.
the hormonal coil can greatly reduce heavy menstrual bleeding.
combined with oestrogen in some menopause treatments to protect the womb lining.
As emergency contraception, levonorgestrel works best the sooner it is taken after unprotected sex and becomes less effective with delay. It does not work if you are already pregnant and does not protect for the rest of the cycle.
How Does Levonorgestrel Work?
For regular contraception, levonorgestrel thickens the mucus at the neck of the womb, thins the womb lining, and, in some methods, helps prevent the release of an egg.
As emergency contraception, it mainly works by delaying or preventing ovulation, so an egg is not released to be fertilised.
In the hormonal coil, it releases progestogen directly into the womb, thinning the lining - which reduces bleeding - and thickening cervical mucus, while in HRT it protects the womb lining from the effects of oestrogen.
Dosages & Administration
The correct dose depends on the type and severity of infection, age, weight, and kidney function. Always follow your clinician's instructions. The table below is for general reference only.
Administration Tips
For daily pills, take at the same time each day and follow the missed-pill advice if a dose is late.
For emergency contraception, take it as soon as possible, and take another dose if you vomit within a few hours; seek advice about ongoing contraception.
Side Effects of Levonorgestrel
Side effects depend on the method but are usually mild. Changes in bleeding are common with progestogen methods.
- Irregular bleeding or spotting
- Headache
- Nausea (especially with emergency contraception)
- Breast tenderness
- Mood changes
- Tiredness or dizziness
- Severe lower abdominal pain (possible ectopic pregnancy, especially after emergency use or with a coil)
- Signs of a blood clot (rare with progestogen-only methods)
- Signs of infection after coil fitting (pain, fever, abnormal discharge)
- Severe allergic reaction
Severe or persistent lower abdominal pain after emergency contraception, or with a coil in place, should be checked promptly, as it can rarely indicate an ectopic pregnancy, which is a medical emergency.
Drug Interactions
Always disclose all prescription drugs, over-the-counter medicines, vitamins, and supplements to your clinician or pharmacist before starting levonorgestrel.
Some epilepsy medicines, rifampicin, and St John's Wort can reduce effectiveness, including of emergency contraception; a higher dose or different method may be advised.
These can affect hormone levels; your clinician will advise on suitability and precautions.
Levonorgestrel and ulipristal should not be used together for the same episode; advice differs between them.
Tell your clinician about other hormones you take so your method can be managed safely.
Important Warnings
Emergency levonorgestrel is a one-off measure, not a regular method. It does not protect for the rest of the cycle, so ongoing contraception should be arranged.
Levonorgestrel methods prevent pregnancy but do not protect against sexually transmitted infections. Use condoms as well if needed.
The hormonal coil is fitted by a trained clinician and carries small risks around fitting, including infection or, rarely, perforation. You will be advised what to watch for.
Your suitability and any new symptoms or medicines should be reviewed periodically, depending on the method used.
Speak to a Clinician About Treatment
Getting advice no longer means sitting in a waiting room. Through The GP Service, you can consult with a licensed clinician in minutes — from home, on your lunch break, or wherever works for you. If treatment is clinically appropriate, your clinician can issue a prescription during the consultation. A consultation does not guarantee a prescription.
The treatment you need, when you need it.
Levonorgestrel FAQs
Yes. Emergency contraception is also available from pharmacies, while regular pills, the coil, and HRT involve a clinician. A licensed clinician can advise and prescribe where appropriate via telehealth.
As soon as possible after unprotected sex. Levonorgestrel emergency contraception becomes less effective the longer you wait, so prompt use matters.
No. Emergency contraception works by delaying ovulation and does not affect an established pregnancy. It is not an abortion method.
The hormonal coil often makes periods much lighter, and some people stop bleeding altogether. Irregular spotting is common in the first months.
If you vomit within a few hours of taking it, you may need another dose. Seek advice promptly to make sure you are still protected.
Levonorgestrel is used with oestrogen in some HRT preparations to protect the womb lining. A clinician can advise whether this suits your menopause treatment.