This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Histamine, 5-HT and PGs, Subject name: Pharmacology
[{'content': 'The drug possessing antagonistic action at histamine, serotonin and muscarinic receptors is: \nSelect and explain. \nA. Promethazine, B. Terfenadine, C. Cyproheptadine, D. Hydroxyzine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: -Cyproheptadine blocks 5HT2A, H1 and muscarinic receptors. -It increases appetite and can be used to promote weight gain in children.', 'role': 'assistant'}]