This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Anatomy
[{'content': 'In deciding on a treatment for a 60 years old patient, Golu, who has chronic hea disease and rheumatoid ahritis, you wish to give him procainamide. He is already taking digoxin, hydrochlohiazide and potassium supplementation. Which of the following is a relevant statement? \nSelect and explain. \nA. A possible drug interaction with digoxin suggests that digoxin blood levels should be obtained before and after staing procainamide., B. Hyperkalemia should be avoided to reduce the likelihood of procainamide toxicity, C. Procainamide cannot be used if the patient has asthma because it has a beta blocking effect, D. Procainamide is not active by the oral route', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Ref: KDT 6/e p512) Hyperkalemia increases the toxicity of class Ia antiarrhythmics.', 'role': 'assistant'}]