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Morphine severe renal impairment — GPhC CRA MCQ

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HardRenal and Hepatic ImpairmentMorphine severe renal impairmentGPhC CRA

A 79-year-old palliative-care patient takes morphine modified-release 30 mg twice daily. His renal function has deteriorated to an estimated GFR of 18 mL/min and he has new drowsiness, confusion and myoclonus. What is the most appropriate action before the next dose?

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Correct answer: B — Withhold the next dose and arrange same-day opioid review before conversion

Morphine-6-glucuronide is active, renally cleared and accumulates in renal impairment. The cited modified-release product should not be administered below a GFR of 20 mL/min because severe prolonged respiratory depression can occur. New drowsiness, confusion and myoclonus are compatible with opioid toxicity. The next dose should therefore be withheld while urgent specialist review selects and safely converts to an alternative; modified-release tablets must not simply be split.

Reference: Morphgesic SR SmPC: https://www.medicines.org.uk/emc/product/4690/smpc