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Theophylline and ciprofloxacin — GPhC CRA MCQ

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HardRespiratory TherapeuticsTheophylline and ciprofloxacinGPhC CRA

A 70-year-old man taking theophylline modified-release tablets for COPD is prescribed ciprofloxacin for suspected prostatitis. He reports previous nausea when his theophylline dose was increased. What is the most important interaction to flag?

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

Ciprofloxacin can increase theophylline concentrations and cause toxicity, including nausea, tremor, arrhythmias, and seizures. The patient already has a history suggesting sensitivity to higher theophylline exposure. The prescriber should consider an alternative antibiotic or arrange monitoring and dose adjustment.

Reference: BNF; SPS