This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
[{'content': 'Respiratory centre depression can be caused by all except: \nSelect and explain. \nA. Opium, B. Strychnine, C. Barbiturates, D. Gelsemium', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ref:Parikh's Textbook of Medical Jurisprudence 6/e p10,57 *Strychnine stimulates the respiratory centre whereas other drugs given the option like opioids, barbiturates and gelsemium cause respiratory depression. *Gelsemium has been traditionally been used to treat pain and respiratory ailments. Toxic symptoms include giddiness, weakness, ptosis, dilated pupils and respiratory depression.", 'role': 'assistant'}]