This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'About lidocaine all are true, except \nSelect and explain. \nA. Dose need to altered in renal failure, B. Loading dose before infusion, C. It is little effected by heat & pH, D. Prolongs refractory period', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Local anaesthetics are poorly water-soluble and this limits their renal excretion to less than 5%. For treating ventricular arrhythmias initial loading dose is to be followed by infusion. The amides are so stable that they are not effected even by autoclaving. Effective refractory period (of cardiac tissue) is prolonged by local anaesthetics.', 'role': 'assistant'}]