First-lineEllaOne

Ulipristal acetate 30 mg (EC)

Selective progesterone receptor modulator (EC)

EC up to 120 h — more effective than levonorgestrel near ovulation.

Oral

First-line for

  • Emergency contraception up to 120 h after UPSI when Cu-IUD declined

Mechanism

Delays LH surge → postpones ovulation by ~5 days.

"UPA delays; LNG only pre-surge"

  • Best from LH rise until peak
  • Vomit within 3 h → re-dose
  • Hold hormonal contraception for 5 d after

Dosing

Dose
30 mg PO single dose within 120 h

Contraindications

  • AbsoluteConfirmed pregnancy
  • CautionSevere asthma on oral steroids

Side effects

  • Headache, nausea
  • Menstrual disturbance
  • Dysmenorrhoea

Fetal & maternal notes

  • Not teratogenic in exposure data; avoid breastfeeding for 1 week (express and discard)

Key interactions

  • Progestogens (including quick-start POP)

    Avoid

    Reduce UPA efficacy — wait 5 days before starting hormonal contraception

  • Enzyme inducers

    Caution

    ↓ efficacy — consider Cu-IUD

Clinical pearls

  • 💡 Not to be given twice in same cycle
  • 💡 Not for BMI > 35 without discussion — Cu-IUD preferred

Content last reviewed: REPLACE_ME (e.g. 2026-07)

Spotted something out of date? See our disclaimer or use Report an Error above.

For educational use only

Not medical advice. Verify dosing against the BNF and your local trust guidelines before prescribing.