This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Pharmacology, Subject name: Pharmacology
[{'content': 'Rifampicin and ritonavir are: \nSelect and explain. \nA. Physical antagonist, B. Chemical antagonist, C. Pharmacokinetic antagonist, D. Competitive antagonist', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. Pharmacokinetic antagonista. Rifampicin is an enzyme inducer of CY3A4 and ritonavir is metabolized by CYP3A4.b. Thus rifampicin can antagonize ritonavir by inducing its metabolism; known as pharmacokinetic antagonism.', 'role': 'assistant'}]