Ceftazidime%25252520avibactam

# Ceftazidime-avibactam ## Overview Ceftazidime-avibactam (AVYCAZ) is a combination cephalosporin antibiotic and non-beta-lactam beta-lactamase inhibitor. It restores the activity of ceftazidime against many Enterobacterales and *Pseudomonas aeruginosa* resistant to ceftazidime alone by inhibiting Ambler class A, C, and some D beta-lactamases (specifically KPC and OXA-48). ## Primary Indications * Complicated intra-abdominal infections (cIAI) (in combination with metronidazole). * Complicated urinary tract infections (cUTI), including pyelonephritis. * Hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP). ## Adult Dosing * **cIAI/cUTI:** 2.5 g (2 g ceftazidime/0.5 g avibactam) IV every 8 hours. * *Duration:* 5–14 days (cIAI, with metronidazole) or 7–14 days (cUTI). * **HABP/VABP:** 2.5 g IV every 8 hours. * *Duration:* 7–14 days. ## Pediatric Dosing Patients 3 months to <18 years: * **cIAI/cUTI/HABP/VABP:** Dosing is weight-based, administered every 8 hours. * *Weight >40 kg:* 2.5 g (2 g/0.5 g). * *Weight 25–40 kg:* 1.25 g (1 g/0.25 g). * *Weight 12–25 kg:* 0.625 g (0.5 g/0.125 g). * *Note:* Safety and efficacy in patients <3 months have not been established. ## Dose Adjustments Must be adjusted for renal impairment (CrCl ≤50 mL/min). * **CrCl 31–50 mL/min:** 1.25 g every 8 hours. * **CrCl 16–30 mL/min:** 0.94 g (0.75 g/0.1875 g) every 12 hours. * **CrCl 6–15 mL/min:** 0.94 g every 24 hours. * **CrCl ≤5 mL/min:** 0.94 g every 48 hours. * *Note:* Avibactam is removed by hemodialysis; administer dose after dialysis on dialysis days. ## Contraindications * Known severe hypersensitivity to ceftazidime, avibactam, or other members of the cephalosporin class. * History of severe beta-lactam anaphylaxis. ## Adverse Effects * **Common:** Nausea, vomiting, diarrhea, constipation, headache, dizziness. * **Serious:** *Clostridioides difficile*-associated diarrhea, hypersensitivity reactions, seizures (primarily in patients with renal impairment receiving excessive dosages). ## Key Drug Interactions * **Probenecid:** May inhibit renal tubular secretion of ceftazidime, increasing plasma concentrations. * **Lab interference:** May cause false-positive results in direct antiglobulin (Coombs) tests. ## Monitoring * Renal function (baseline and during therapy). * Signs of *C. difficile* diarrhea. * Neurological status (especially in patients with renal impairment). * Clinical response (fever, WBC count, site-specific symptoms). ## Clinical Pearls * **Metronidazole Requirement:** For cIAI, metronidazole must be added to provide anaerobic coverage. * **Spectrum:** Does not cover *Acinetobacter* spp. or most metallo-beta-lactamase (MBL) producing organisms (e.g., NDM-1). * **Stability:** Once reconstituted, the solution should be used within 12 hours if stored at room temperature or 24 hours if refrigerated. * **Local Protocols:** Always verify dosing against specialized institutional antibiograms and renal dosing guidelines, as specific concentrations for pediatric populations may vary by hospital policy. *** *Educational Disclaimer: This information is for educational purposes only and does not constitute medical advice. Clinicians must verify the most current prescribing information (FDA package insert or local hospital formulary) before administering medication.*