Other b-lactam antibiotics
Start with the big picture
β-lactams bind penicillin-binding proteins and inhibit peptidoglycan cross-linking, leading to bactericidal activity. Carbapenems are broad-spectrum agents, but their individual coverage differs: ertapenem lacks activity against Pseudomonas and Acinetobacter, while imipenem is given with cilastatin and meropenem has a lower seizure risk than imipenem. Aztreonam targets aerobic Gram-negative bacteria, including Pseudomonas, without Gram-positive or anaerobic activity. β-lactamase inhibitors have little intrinsic antibacterial effect; paired with β-lactams, they can extend activity against enzyme-producing organisms. Resistance may involve carbapenemases, altered porins, efflux pumps, or mutated PBPs. The deeper lesson organizes these agents by mechanism, spectrum, safety, combinations, and pharmacokinetic considerations.
What you'll learn
- Explain how β-lactams inhibit bacterial cell-wall synthesis.
- Compare the coverage and distinguishing features of individual carbapenems.
- Describe aztreonam’s target range and key clinical considerations.
- Explain how β-lactamase inhibitors expand partner-drug activity.
- Identify resistance mechanisms relevant to these antibiotics.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
