This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy: General Principles, Subject name: Pharmacology
[{'content': 'Sparfloxacin and astemizole can cause: \nSelect and explain. \nA. Ventricular arrhythmia, B. Myopathy, C. Electrolyte imbalance, D. Nephropathy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (A) Ventricular arrhythmia(Ref: KDT 8/e p764)Both sparfloxacin and astemizole blocks cardiac K+ channels in high concentration. This property may result in torsades de pointes (polymorphic ventricular tachycardia).Other drugs causing torsades de pointes are:TerfenadineCisaprideZiprasidoneGrepafloxacin', 'role': 'assistant'}]