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Emergency Contraceptive (Progestogen)

Levonorgestrel (Emergency Contraception)

Brand names: Levonelle 1500, Upostelle, Ezinelle

Levonorgestrel is a progestogen used as emergency contraception after unprotected sex or contraceptive failure. It is effective when taken up to 72 hours afterwards, and the sooner it is taken the more effective it is.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

Take one tablet daily by mouth at the same time every day for 91 days. (2.1) Take tablets in the order directed on the Extended-Cycle Wallet. (2.2) 2.1 How to Start and Take Iclevia Iclevia is dispensed in an Extended-Cycle Wallet [see How Supplied/Storage and Handling (16) ]. Iclevia should be started on a Sunday (see Table 1). For the first cycle of a Sunday Start regimen, an additional method of contraception should be used until after the first 7 consecutive days of administration. Table 1: Instructions for Administration of Iclevia Starting Iclevia in females with no current use of hormonal contraception (Sunday Start) Important: Consider the possibility of ovulation and conception …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2024-07-02. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It works mainly by delaying or inhibiting ovulation; it is not an abortifacient and does not disrupt an established pregnancy.

Prescribing in practice

  • It does not provide ongoing contraception for the rest of the cycle, so reliable contraception must be continued or started.
  • A larger dose or an alternative (ulipristal acetate or a copper intrauterine device) may be advised at higher body weight or after enzyme-inducing drugs.
  • It can be used more than once in a cycle if needed, but a copper intrauterine device is the most effective emergency option.

Monitoring

No routine monitoring is required; advise a pregnancy test if the next period is more than a few days late or is unusually light, and arrange ongoing contraception.

Counselling the patient

  • Take it as soon as you can after unprotected sex, as it works better the earlier it is taken.
  • If you vomit within a couple of hours of the dose, seek advice as you may need to repeat it.
  • Use condoms or abstain until you start or restart reliable contraception, and do a pregnancy test if your period is late.

Evidence & guidelines

Recommended emergency contraceptive option (FSRH; NICE CKS).

Reference: FSRH Emergency Contraception Guideline 2017 (updated 2023); NICE; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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