Clarithromycin statin — GPhC CRA MCQ
Instant feedback + full explanation. One question, done properly.
Educational content. Not a substitute for clinical judgement or local policy.
Reveal the answer and explanation
Correct answer: E — Use an alternative antibiotic or withhold simvastatin during clarithromycin treatment
Use an alternative antibiotic or withhold simvastatin during clarithromycin treatment: Clarithromycin strongly inhibits CYP3A4 and can markedly increase simvastatin exposure, myopathy and rhabdomyolysis risk. Continue both medicines with simvastatin moved to morning administration: Changing time does not prevent persistent CYP3A4 inhibition. Reduce simvastatin to 20 mg on the first clarithromycin treatment day: Even a reduced simvastatin dose should not be co-administered with clarithromycin. Separate simvastatin and clarithromycin administration by at least twelve hours: The metabolic inhibition persists throughout the dosing interval. Increase simvastatin during clarithromycin treatment and monitor muscle symptoms: Clarithromycin raises simvastatin exposure and dose escalation would increase toxicity.
Reference: BNF: simvastatin: https://bnf.nice.org.uk/drugs/simvastatin/; BNF: clarithromycin: https://bnf.nice.org.uk/drugs/clarithromycin/