This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Opioids and Alcohols, Subject name: Pharmacology
[{'content': 'Long term use of pethidine is avoided because a metabolite of pethidine is associated with: \nSelect and explain. \nA. Constipation, B. Dependence, C. Seizures, D. Respiratory depression', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Pethidine is mainly metabolized by hydrolysis to meperidinic acid but a minor pathway of metabolism involving methylation to nor-pethidine is also present. In overdose of pethidine, this minor pathway assumes impoance and there is accumulation of nor-pethidine. This compound possesses excitatory propeies and can lead to tremors, mydriasis, delirium, myoclonus and convulsions.', 'role': 'assistant'}]