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Combined oral contraceptive (1st-generation progestogen)

Ethinylestradiol with norethisterone

Brand names: Ovysmen, Loestrin, Brevinor

Adult dose

Dose: 1 tablet OD per pack regimen
Route: Oral
Frequency: OD

Clinical pearls

  • FSRH-recommended low-VTE-risk progestogen alongside levonorgestrel for first-line CHC choice
  • Useful in women preferring well-established formulations

Contraindications

  • Standard CHC contraindications

Side effects

  • Breakthrough bleeding
  • VTE (low — comparable to levonorgestrel)
  • Headache
  • Mood change
  • Acne (less anti-androgenic than newer)

Interactions

  • Enzyme inducers
  • Lamotrigine

Monitoring

  • BP
  • Migraine status
  • BMI

Reference: BNF; FSRH CHC guideline; UKMEC; MHRA Drug Safety Update; https://bnf.nice.org.uk/drugs/ethinylestradiol-with-norethisterone/. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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