This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
The most impoant advese effect of sotalol is? 
Select and explain. 
A. Torsades de pointes, B. Hea block, C. Pulmonary fibrosis, D. Vomiting
A: Torsades de pointes
Answer: A: Torsades de pointes 
Explanation: Ans. is 'a' i.e., Torsades de pointes Sotalol It is a nonselective -blocker. It prolongs the action potential (class 3 antiarrhythmic). Sotalol is well absorbed orally with bioavailibility of 100%. It is not metabolized in liver. Excretion is predominantly by kidney in the unchanged form. The most significant cardiac adverse effect is dose related torsade de points. (Polymorphic ventricualr tachycardia).