Question
III generation cephalosporin
Answer
Third-generation cephalosporins are beta-lactam antibiotics with substantially expanded Gram-negative coverage.
Examples: Ceftriaxone, Cefotaxime, Ceftazidime (the latter specifically adding Pseudomonas coverage).
MOA: bind penicillin-binding proteins, inhibiting bacterial cell wall (peptidoglycan) synthesis — bactericidal.
Uses: excellent CNS penetration makes ceftriaxone/cefotaxime mainstays of empirical bacterial meningitis therapy; also used for severe Gram-negative sepsis, community-acquired pneumonia, gonorrhea (ceftriaxone), and complicated urinary tract infections.
Adverse effects: hypersensitivity reactions (partial cross-reactivity with penicillin allergy), biliary sludging (ceftriaxone specifically), disulfiram-like reaction with alcohol (agents containing an N-methylthiotetrazole side chain).

