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Theophylline interaction — GPhC CRA MCQ

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HardRespiratory TherapeuticsTheophylline interactionGPhC CRA

A 58-year-old woman taking modified-release theophylline for COPD is prescribed ciprofloxacin for a urinary tract infection. She has previously had palpitations with high theophylline levels. What is the most important interaction to flag?

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Correct answer: C — Ciprofloxacin may increase theophylline concentration and toxicity

Ciprofloxacin can increase theophylline concentrations and risk toxicity, including nausea, tremor, palpitations and seizures. This is clinically important in a patient with previous toxicity. The prescription should be queried and an alternative antibiotic considered if suitable.

Reference: BNF