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: Medicine
A patient has serum creatinine of 150-300 micromol/L. Which of the following require dosage reduction: March 2011 
Select and explain. 
A. Ampicillin, B. Isoniazid, C. Gentamycin, D. Penicillin
C: Gentamycin
Answer: C: Gentamycin 
Explanation: Ans. C: Gentamycin Drugs whose dosage are affected in mild renal insufficiency (GFR 20-50 mL/ min or serum creatinine 150-300 micromol/L) are: ACE inhibitors, Aminoglycosides, chlorpropamide, digoxin, fibrates, lithium and zidovudine