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Theophylline interaction — GPhC CRA MCQ

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HardRespiratory TherapeuticsTheophylline interactionGPhC CRA

A 62-year-old woman with COPD takes theophylline modified-release 300mg twice daily. She is prescribed ciprofloxacin for a urinary tract infection by an out-of-hours prescriber. What is the most important interaction to flag?

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Correct answer: C — Ciprofloxacin may increase theophylline levels and toxicity risk

Ciprofloxacin can increase theophylline exposure and the risk of toxicity such as nausea, tremor, arrhythmia and seizures. The combination should be avoided or carefully managed. The pharmacist should contact the prescriber for an alternative antibiotic or monitoring plan. The other options do not describe the key interaction.

Reference: BNF