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 patient with ischemic heart disease, diagnosed with migraine; indicated drug in this case is: \nSelect and explain. \nA. Propranolol, B. Triptans, C. Ergotamines, D. Butorphanol', 'role': 'user'}, {'content': 'Answer: D \nExplanation: For patients with a history of CAD, triptans or ergotamine are contra-indicated,\xa0therefore opioids like intranasal butorphanol should be used for acute severe migraine.', 'role': 'assistant'}]