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: Medicine
[{'content': 'All are used in bronchial asthma, except: \nSelect and explain. \nA. Salbutamol, B. Morphine, C. Aminophylline, D. Steroid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Morphine is a drug of emergency, but due care has to be taken in its use.\xa0\n\nInfants and the elderly are more susceptible to the respiratory depressant action of morphine.\xa0\nIt is dangerous in patients with respiratory insufficiency (emphysema, pulmonary fibrosis, cor pulmonale); sudden deaths have occurred. Morphine accentuates sleep apnoea; hypoxic brain damage can occur.\xa0\nBronchial asthma: Morphine can precipitate\xa0an attack by its histamine releasing action.\xa0A high potency opioid with lower histamine\xa0releasing potential (e.g. fentanyl) should be\xa0used, if unavoidable, in an asthmatic.\xa0\nHead injury: Morphine is contraindicated in patients with head injury. Reasons are—\n\n\nBy retaining CO2, it increases intracranial tension which will add to that caused by head injury itself.\xa0\nEven therapeutic doses can cause marked respiratory depression in these patients.\xa0\nVomiting, miosis and altered mentation produced by morphine interfere with assessment of progress in head injury cases.\xa0\n\nReference: Essentials of Medical Pharmacology Eighth Edition KD\xa0 TRIPATHI\xa0 page no 502', 'role': 'assistant'}]