Which class is an example of time-dependent antibiotics?

Which class is an example of time-dependent antibiotics?

• A. Aminoglycosides.
• B. Fluoroquinolones.
• C. Beta-lactams.
• D. Macrolides.

Answer: (C)

Time-dependent antibiotics rely on keeping the drug concentration above the MIC for as long as possible within each dosing interval. Their ability to kill bacteria improves with longer exposure above the MIC rather than with higher peak levels. Beta-lactams—penicillins, cephalosporins, and related agents—are classic examples. Their bactericidal effect is strongest when drug levels stay above the MIC for a critical portion of each dose interval, so extending infusion times or dosing frequency to maintain T>MIC maximizes efficacy. By contrast, aminoglycosides and fluoroquinolones are typically more effective with higher peak concentrations relative to MIC, and macrolides are often treated with considerations similar to time-dependent exposure. Therefore, beta-lactams best fit the time-dependent category.

Time-dependent antibiotics rely on keeping the drug concentration above the MIC for as long as possible within each dosing interval. Their ability to kill bacteria improves with longer exposure above the MIC rather than with higher peak levels. Beta-lactams—penicillins, cephalosporins, and related agents—are classic examples. Their bactericidal effect is strongest when drug levels stay above the MIC for a critical portion of each dose interval, so extending infusion times or dosing frequency to maintain T>MIC maximizes efficacy. By contrast, aminoglycosides and fluoroquinolones are typically more effective with higher peak concentrations relative to MIC, and macrolides are often treated with considerations similar to time-dependent exposure. Therefore, beta-lactams best fit the time-dependent category.