Ceftazidime%252525252525252520avibactam

# Ceftazidime-avibactam ## Overview Ceftazidime-avibactam (AVYCAZ) is a combination cephalosporin antibiotic and non-beta-lactam beta-lactamase inhibitor. Avibactam inhibits Class A (ESBL, KPC), Class C (AmpC), and certain Class D (OXA-48) beta-lactamases, restoring ceftazidime’s activity against many resistant Gram-negative organisms. ## Primary Indications * Complicated intra-abdominal infections (in combination with metronidazole). * Complicated urinary tract infections (cUTIs), including pyelonephritis. * Hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP). ## Adult Dosing Standard dose (for CrCl >50 mL/min): 2.5 g (ceftazidime 2 g / avibactam 0.5 g) IV every 8 hours. Infuse over 2 hours. * For cIAI: Must be administered with metronidazole. ## Pediatric Dosing Approved for patients $\ge$ 3 months of age based on weight/age dosing (refer to product labeling or institutional protocol). * **3 months to <6 months:** 40 mg/kg (ceftazidime component) every 8 hours. * **6 months to <18 years and <50 kg:** 50 mg/kg (ceftazidime) every 8 hours. * **$\ge$ 18 years and $\ge$ 50 kg:** 2.5 g every 8 hours. ## Dose Adjustments Renal impairment requires dose reduction based on estimated CrCl (Cockcroft-Gault). * **CrCl 31–50 mL/min:** 1.25 g every 8 hours. * **CrCl 16–30 mL/min:** 0.94 g (ceftazidime 750 mg / avibactam 187.5 mg) every 12 hours. * **CrCl 6–15 mL/min:** 0.94 g every 24 hours. * **CrCl $\le$ 5 mL/min:** 0.94 g every 48 hours. * **End-stage renal disease (ESRD):** Dose after dialysis. ## Contraindications * Known hypersensitivity to ceftazidime, avibactam, or other beta-lactam antibacterial drugs (anaphylaxis). ## Adverse Effects * **Common:** Nausea, vomiting, constipation, diarrhea, anxiety, dizziness. * **Serious:** *Clostridioides difficile*-associated diarrhea, seizures (especially with renal impairment/overdose), hypersensitivity reactions. ## Key Drug Interactions * **Probenecid:** Inhibits renal excretion of ceftazidime; avoid concomitant use. * **Laboratory Interference:** May cause false-positive direct antiglobulin (Coombs) test; potential for false-positive urine glucose results with non-enzymatic methods. ## Monitoring * Renal function (CrCl) to ensure appropriate dosing. * Signs/symptoms of *C. difficile* infection. * Neurological status, specifically in patients with impaired renal function (risk of neurotoxicity/seizures). ## Clinical Pearls * **Spectrum:** Does not provide activity against anaerobic bacteria; metronidazole is required for cIAI. * **Extended Infusion:** The 2-hour infusion time is critical to optimize time above the MIC ($T > fMIC$), particularly for resistant isolates. * **Uncertainty:** Effectiveness against metallo-beta-lactamase (MBL) producing organisms (e.g., NDM-1) is poor; consider alternative agents like aztreonam if MBL is suspected or confirmed. Always follow your institutional antibiotic stewardship guidelines for use. *** *Disclaimer: This information is for educational purposes only. Hospital protocols and clinical judgment vary. Always verify current prescribing information, dosing, and compatibility via institutional electronic health records or official FDA package inserts before administration.*