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': 'Which of the following about phenytoin is true ? \nSelect and explain. \nA. It follows zero order kinetics, B. Not an hepatic enzyme inducer, C. It is excreted unchanged in urine, D. It is not teratogenic', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., It follows zero order kinetics Phenytoin is metabolized in liver by hydroxylation and glucuranide conjugation (option 'c' is incorrect) o This drug follows saturation kinetics (kinetics changes from first order to zero order within therapeutic concentrations) Phenytoin is an enzyme inducer and induces the metabolism of many drugs. Phenytoin is a known teratogenic and produces fetal hydantoin syndrome.", 'role': 'assistant'}]