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Antibiotics and OCP Interaction — ORE Part 1 MCQ

Instant feedback + full explanation. One question, done properly.

ModeratePharmacology & TherapeuticsAntibiotics and OCP InteractionORE Part 1

A 30-year-old woman takes a combined oral contraceptive pill and is prescribed amoxicillin for an acute dental infection. She has no vomiting or diarrhoea. Which advice is most appropriate?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: AContinue the pill as usual; no additional contraception is routinely required

A is correct. Amoxicillin is a non-enzyme-inducing antibiotic. Current UK contraception guidance does not recommend additional contraceptive precautions with non-enzyme-inducing antibiotics used alongside combined hormonal contraception. The important exception is impaired absorption: if the illness or antibiotic causes vomiting or diarrhoea, missed-pill guidance and additional precautions may be needed. B and D reflect outdated routine advice for ordinary antibiotics. C is unnecessary and may itself create a risk of contraceptive failure. E has no role and could increase adverse effects. Clinically significant antibiotic-related reduction in combined-pill efficacy is associated with enzyme-inducing agents, notably rifampicin and rifabutin, not routine dental amoxicillin or metronidazole.

Reference: NHS Dumfries and Galloway. Possible drug interactions: Combined hormonal contraception, Antibiotics section. Reviewed 31 January 2024. https://www.rightdecisions.scot.nhs.uk/nhs-dumfries-galloway-refhelp/sexual-health/contraception/combined-hormonal-contraception/possible-drug-interactions/