Antibiotic classification: implications for drug selection.

This article presents a useful antibiotic classification model for the busy clinician who must select agents for patients in the critical care setting. The model organizes antibiotics based on their mechanism of action, ie, cell-wall inhibitors, nucleic acid inhibitors, and protein-synthesis inhibitors; clinicians are encouraged to further segregate agents within the broader categories by generation. An overview of the antimicrobial spectrum for each class is presented, and important differences within individual classes are highlighted. The most common indications for each antibiotic class are reviewed, and key pharmacokinetic characteristics that help distinguish one drug from another are outlined.