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: Psychiatry
[{'content': 'A 25 year old man with a psychotic illness, was treated with haloperido130mg/day. On the third day, he developed pacing, and inability to sit still in one place. The medication likely to be helpful is - \nSelect and explain. \nA. Phenytoin, B. Propranolol, C. Methylphenidate, D. Trihexyphenedyl', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Restlessness (inability to sit still) and pacing suggests the diagnosis of Akathesia.\nThe drug of choice for Akathesia is one of the β-blocker.', 'role': 'assistant'}]