A patient with Gram-negative sepsis is treated with gentamicin. Which pharmacokinetic/pharmacodynamic index best predicts bactericidal efficacy?
- A Time above MIC
- B AUC/MIC
- C Cmax/MIC ✓
- D Post-antibiotic effect duration
Correct answer: C. Cmax/MIC
Explanation
Aminoglycosides exhibit concentration-dependent killing and a prolonged post-antibiotic effect. The Cmax/MIC ratio (peak concentration to minimum inhibitory concentration) is the best predictor of efficacy, guiding once-daily dosing. Time above MIC is more relevant for beta-lactams.
Reference: Katzung: Basic & Clinical Pharmacology, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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