Ceftazidime

# Ceftazidime ## Overview Third-generation cephalosporin with broad-spectrum gram-negative activity, including *Pseudomonas aeruginosa*. Bactericidal via inhibition of cell wall synthesis. Poor activity against gram-positive and anaerobic bacteria. ## Primary Indications - Hospital-acquired pneumonia (including ventilator-associated) - Febrile neutropenia (in combination) - Complicated urinary tract infections - Intra-abdominal infections (with anaerobic coverage) - *Pseudomonas* infections - Meningitis (gram-negative) ## Adult Dosing - **Usual**: 1–2 g IV every 8 hours - **Severe infections (e.g., meningitis, *Pseudomonas* pneumonia)**: 2 g IV every 8 hours - **Maximum**: 6 g/day (higher doses may be used in cystic fibrosis per protocol) ## Pediatric Dosing - **Neonates (0–28 days)**: 30 mg/kg IV every 12 hours (adjust per gestational age) - **Infants/Children (1 month–12 years)**: 30–50 mg/kg IV every 8 hours; **max** 6 g/day - **Meningitis**: 50 mg/kg IV every 8 hours; **max** 6 g/day ## Dose Adjustments - **Renal impairment** (CrCl <50 mL/min): Reduce dose and/or extend interval. Exact dosing per local protocol (e.g., 1 g every 12–48 hours depending on CrCl). - **Hemodialysis**: Administer after dialysis; supplemental dose may be needed. - **Hepatic impairment**: No adjustment required. ## Contraindications - Hypersensitivity to ceftazidime or any cephalosporin - Severe immediate hypersensitivity to penicillins (cross-reactivity risk) ## Adverse Effects - **Common**: Diarrhea, nausea, rash, phlebitis at injection site - **Serious**: *Clostridioides difficile* colitis, hypersensitivity reactions (including anaphylaxis), seizures (especially with high doses in renal impairment), neutropenia, thrombocytopenia ## Key Drug Interactions - **Probenecid**: Decreases ceftazidime renal excretion (increases levels) - **Aminoglycosides**: Synergistic for *Pseudomonas*; monitor renal function - **Loop diuretics**: May increase nephrotoxicity risk (controversial) ## Monitoring - Renal function (baseline and periodic) - CBC with differential (prolonged therapy) - Signs of superinfection or *C. difficile* diarrhea - Therapeutic drug monitoring not routinely required ## Clinical Pearls - Inactivated by extended-spectrum beta-lactamases (ESBLs); not reliable for ESBL-producing organisms. - Use with metronidazole for anaerobic coverage in intra-abdominal infections. - Compatible in IV solutions with aminoglycosides but do not mix in same bag. - For febrile neutropenia, often combined with an aminoglycoside or antipseudomonal fluoroquinolone. --- *This information is for educational purposes only. Always verify current prescribing information, local protocols, and patient-specific factors before use.*