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
Sparfloxacin and astemizole can cause: 
Select and explain. 
A. Ventricular arrhythmia, B. Myopathy, C. Electrolyte imbalance, D. Nephropathy
A: Ventricular arrhythmia
Answer: A: Ventricular arrhythmia 
Explanation: 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