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 drug used in treating leprosy acts as a bactericidal agent? \nSelect and explain. \nA. Clofazimine, B. Dapsone, C. Rifampicin, D. Ethionamide', 'role': 'user'}, {'content': "Answer: C \nExplanation: Dapsone, rifampicin and clofazimine are WHO recommended drugs used in the treatment of leprosy. Among these only rifampicin is bactericidal. Rifampin binds to the beta subunit of bacterial DNA-dependent RNA polymerase and thereby inhibits RNA synthesis. It is bactericidal, it penetrates most tissues and into phagocytic cells. Indications: Treatment of tuberculosis along with other antimycobacterial drugs. Used to eliminate meningococcal carriage Leprosy Prophylaxis in contacts of children with Haemophilus influenzae type b disease In combination with a second agent is used to eradicate staphylococcal carriage In serious staphylococcal infections such as osteomyelitis and prosthetic valve endocarditis Ref: Gelber R.H. (2012). Chapter 166. Leprosy. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.", 'role': 'assistant'}]