ceftazidime

Brand: Fortaz, Tazicef

Prototype Drug
Drug Class: third-generation cephalosporin
Drug Family: antibiotic
Subclass: anti-pseudomonal third-generation cephalosporin
Organ Systems: infectious-disease

Mechanism of Action

Inhibits bacterial cell wall synthesis; uniquely active against Pseudomonas aeruginosa among third-generation cephalosporins; excellent gram-negative coverage.

penicillin-binding proteins (PBPs)

Indications

  • Pseudomonas aeruginosa infections
  • hospital-acquired pneumonia
  • septicemia
  • urinary tract infections (complicated)
  • meningitis (gram-negative)
  • febrile neutropenia

Contraindications

  • cephalosporin hypersensitivity

Adverse Effects

Common

  • injection site reactions
  • diarrhea
  • elevated LFTs

Serious

  • anaphylaxis
  • C. difficile colitis
  • seizures (high doses, renal impairment)
  • superinfection with resistant organisms

Pharmacokinetics (ADME)

Absorption IV/IM only
Distribution widely distributed; good CNS penetration
Metabolism not metabolized
Excretion renal (unchanged >80%); dose adjustment critical in renal impairment
Half-life 1.8 hours (normal renal function)
Onset immediate (IV)
Peak 1 hour (IM)
Duration 8 hours
Protein Binding 10–17%
Vd moderate

Drug Interactions

Drug / Agent Mechanism Severity
aminoglycosides synergistic against Pseudomonas; additive nephrotoxicity moderate
chloramphenicol antagonism of bactericidal activity (in vitro) moderate

Nursing Considerations

  1. Dose reduction is essential in renal impairment; reduce dose and/or extend interval when CrCl is <50 mL/min; monitor for neurotoxicity (encephalopathy, seizures) with accumulation.
  2. Monitor cultures for resistance development; Pseudomonas aeruginosa can develop resistance during therapy via AmpC derepression.
  3. Administer IV over 15–30 minutes; reconstituted solutions may be used within 24 hours at room temperature.
  4. Monitor renal function, CBC, and LFTs during prolonged therapy.

Clinical Pearls

  • Ceftazidime is one of the standard agents for Pseudomonas aeruginosa infections, with better anti-pseudomonal activity than ceftriaxone but no anaerobic coverage.
  • Ceftazidime-avibactam, a newer combination, extends coverage to KPC and OXA-48 carbapenemase-producing organisms, critical for multidrug-resistant pathogens.

Safety Profile

Pregnancy generally-safe
Lactation use-with-caution
Renal Adjustment Required
Hepatic Adjustment Not required
TDM Not required