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': 'Most common side effect of 5-HT 3 antagonist drug alosetron is ? \nSelect and explain. \nA. Pulmonary fibrosis, B. Cardiac arhythymmias, C. Constipation, D. Headache', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Constipation Alosetron has sometimes caused fatal intestinal side effects including constipation and ischemic colitis.", 'role': 'assistant'}]