Levonorgestrel (emergency contraception)
1.5 mg orally as one dose, ideally within 72 hours of unprotected sex (3 mg if on enzyme-inducing drugs or BMI over 26 in some guidance).
Common brands in Pakistan: Postinor. Brand availability changes; check with your pharmacy.
On this page
Dose
1.5 mg orally once, as soon as possible and within 72 hours. Repeat if vomited within 3 hours. A double dose (3 mg) is used with enzyme-inducing drugs.
Notes
- Less effective with time and in higher body weight; a copper IUD is the most effective option (up to 5 days).
- Next period may be early or late; do a pregnancy test if over 7 days late.
- Doesn't end an existing pregnancy.
Frequently asked questions
How long after sex does levonorgestrel work?
Licensed up to 72 hours; the sooner, the better.
Used in these guides
Sources
Doses on this page are typical doses from the sources above. Always confirm with a current drug reference, the product leaflet and your hospital protocol, especially in children, pregnancy and kidney or liver disease.
For FCPS Part 1
Revising for FCPS Part 1? Levonorgestrel is covered in our textbook chapter Hormonal contraceptives and HRT, with practice MCQs.