Ceftazidime%2525252525252525252525252525252520avibactam

# Ceftazidime-avibactam ## Overview Ceftazidime-avibactam (AVYCAZ) is a combination cephalosporin antibiotic with a non-beta-lactam beta-lactamase inhibitor. Avibactam protects ceftazidime from hydrolysis by class A (ESBL, KPC), class C (AmpC), and some class D beta-lactamases. ## 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 (ceftazidime 2 g/avibactam 0.5 g) IV every 8 hours. Duration: 5–14 days. * **HABP/VABP:** 2.5 g IV every 8 hours. Duration: 7–14 days. * **Maximum:** 2.5 g every 8 hours. ## Pediatric Dosing * **Patients 3 months to <18 years:** * Dosing is weight-based. Refer to institutional antimicrobial stewardship guidelines or the FDA label for specific age/weight-based mg/kg calculations. * Generally: 50 mg/kg (ceftazidime) / 12.5 mg/kg (avibactam) IV every 8 hours, up to a maximum dose of 2.5 g. ## Dose Adjustments * **Renal Impairment:** Requires dose reduction based on CrCl (Cockcroft-Gault). * CrCl 31–50 mL/min: 1.25 g every 8 hours. * CrCl 16–30 mL/min: 0.94 g (0.75 g ceftazidime/0.1875 g avibactam) every 12 hours. * CrCl 6–15 mL/min: 0.94 g every 24 hours. * CrCl ≤5 mL/min: 0.94 g every 48 hours. * **Renal Replacement Therapy:** Dosing depends on modality (e.g., HD vs. CRRT). Consult local infectious disease protocols or clinical pharmacists for CRRT adjustments. ## Contraindications * Known severe hypersensitivity to ceftazidime, avibactam, or other beta-lactams. * History of severe allergic reactions (e.g., anaphylaxis) to any other cephalosporin, penicillin, or carbapenem. ## Adverse Effects * **Common:** Nausea, vomiting, diarrhea, constipation, headache, dizziness. * **Serious:** *Clostridioides difficile*-associated diarrhea, seizures (most common in patients with renal impairment receiving inappropriately high doses), C-reactive protein increases, and hypersensitivity reactions. ## Key Drug Interactions * **Probenecid:** May increase serum concentrations of ceftazidime; avoid concomitant use. * **Ertapenem:** Clinical evidence suggests Ceftazidime-avibactam might conflict with susceptibility testing of ertapenem in specific resistant organisms (uncommon in clinical practice but relevant for micro-lab/ID consults). ## Monitoring * **Baseline:** Renal function (CrCl). * **Ongoing:** Monitor for signs of *C. difficile* infection, hypersensitivity symptoms, and seizure activity (especially in patients with renal dysfunction). * **Renal clearance:** Adjust dose promptly if renal function declines. ## Clinical Pearls * Ceftazidime-avibactam does **not** provide anaerobic coverage; must be combined with metronidazole for cIAI. * It is a core agent for carbapenem-resistant *Enterobacteriaceae* (CRE). * Always confirm susceptibility via microbiology reports if available, as clinical success depends on the resistance mechanism (e.g., ineffective against metallo-beta-lactamases like NDM). * Dosing is often managed via institutional protocols; verify renal adjustment schedules against your pharmacy's current guidelines. *** **Educational Disclaimer:** This information is for educational purposes only. Always consult your institution’s clinical guidelines, local antibiogram, and the official FDA/EMA prescribing information before administering any medication.