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Macrolide and QT prolongation — GPhC CRA MCQ

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HardDrug InteractionsMacrolide and QT prolongationGPhC CRA

A patient taking sotalol is prescribed erythromycin for a respiratory infection. Their last ECG showed a prolonged QT interval. What is the most important interaction to flag?

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Correct answer: E — Additive QT prolongation and arrhythmia risk

Sotalol and erythromycin can both prolong the QT interval and increase risk of serious arrhythmia. Previous QT prolongation makes the interaction particularly significant. The prescriber should consider an alternative antibiotic. The patient should seek urgent help for syncope or palpitations.

Reference: https://www.pharmacyregulation.org/registration-assessment#stage-8-order-34