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Spironolactone hyperkalaemia — GPhC CRA MCQ

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HardCardiovascular TherapeuticsSpironolactone hyperkalaemiaGPhC CRA

A patient with HFrEF started spironolactone 25 mg daily one week ago. Potassium has risen from 4.6 to 5.7 mmol/L; renal function is stable and there are no ECG changes. Which action best matches UK monitoring guidance?

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

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Correct answer: C — Reduce to 25 mg on alternate days; repeat bloods in one week

After initiation or dose change in heart failure, renal function and electrolytes are checked after one week and monthly for the first three months. Potassium between 5.5 and below 6.0 mmol/L calls for dose reduction; SPS gives 25 mg daily to 25 mg on alternate days as an example. Potassium at or above 6.0 mmol/L instead triggers stopping spironolactone and seeking specialist advice.

Reference: NHS SPS spironolactone monitoring: https://www.sps.nhs.uk/monitorings/spironolactone-monitoring/