Pharmacology 2 Block 2: Inhibitors of Bacterial Cell Wall Synthesis

Penicillin G

MOA: Narrow-spectrum penicillin; activity against Strep species and enterococcus
Use: Syphilis, meningitis

Nafcillin

MOA: Penicillinase-resistant penicillin
Use: Osteomyelitis

Amoxicillin

MOA: Narrow-spectrum aminopenicillin; inhibits penicillin-binding protein; activity against Strep and enterococcus
Use: Upper respiratory tract infections and otitis media

Augmentin (Amoxicillin/Clavulanate)

MOA: Extended-spectrum penicillin + beta-lactamase inhibitor; destroys beta-lactamase enzyme produced by bacteria
Use: Upper respiratory tract infections caused by H. influenzae and M. catarrhalis

Cephalexin

MOA: First-generation cephalosporin
Use: Skin and soft tissue infections, cellulitis
SE: No MRSA coverage

Ceftriaxone

MOA: Third-generation cephalosporin
Use: Gonorrhea, UTIs, pneumonia
SE: IV only

Cefepime

MOA: Fourth-generation cephalosporin, broad spectrum
Use: Drug-resistant gram-negative infections (UTI, pneumonia)
SE: IV only

Imipenem

MOA: Carbapenem, broad spectrum
Use: Advanced multi-drug resistant infections

Bacitracin

MOA: Bacterial cell wall synthesis inhibitor
Use: Skin and eye infections; activity against strep and staph
SE: Topical only, used in triple therapy

Fosfomycin

MOA: Bacterial cell wall synthesis inhibitor
Use: Lower UTIs; activity against E. coli and enterococcus
SE: Only reaches adequate concentrations in bladder; use only for mild UTI; long half-life allows one-time dose

Vancomycin

MOA: Bacterial cell wall synthesis inhibitor
Use: Bone and joint infections; MRSA coverage
SE: IV only; requires blood monitoring with drug trough