This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
A middle aged man with chronuc renal failure is diagnostic to have sputum positive pulmonary tuberculosis. His creatinine clearance is 25ml /min. All of the following drugs need modification in doses except 
Select and explain. 
A. Isoniazid, B. Streptomycin, C. Rifamipicin, D. Ethambutol
C: Rifamipicin
Answer: C: Rifamipicin 
Explanation: Refer Katzung 11/e p826 Rifamipicin is associated with bile Rifamipicin is secreted in bile So it does not require dose adjustment min renal failure