This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
[{'content': 'The drug not used in acute asthma is \nSelect and explain. \nA. Salbutomol, B. Ipratropium, C. Montelukast, D. Hydrocoisone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Refer KDT 6/e p 222 Only bronchodilator drugs are useful for the treatment of acute attack of asthma Beta 2 agonists eg salbutomol, terbutaline. Antichokinergics eg Iprqtropoum, tiotropium Methylxanthine eg Theophylline', 'role': 'assistant'}]