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
[{'content': 'A machinery worker in a factory has profuse rhinorrhea and sneezing. Which among the following is the best drug to be given to him? \nSelect and explain. \nA. Diphenhydramine, B. Cetrizine, C. Promethazine, D. Hydroxyzine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: First-generation antihistaminic drugs can penetrate the blood brain barrier and thus result in sedation and psychomotor\xa0impairment. Therefore, these drugs are contraindicated in persons requiring constant attention\xa0(like truck drivers, machinery operators and swimmers)', 'role': 'assistant'}]