Recommended Dosage of Ceftazidime/Avibactam
The standard recommended dosage of ceftazidime/avibactam for adults with normal renal function is 2.5 grams (ceftazidime 2 grams and avibactam 0.5 grams) administered every 8 hours by intravenous infusion over 2 hours. 1
Adult Dosing
- For adults with creatinine clearance (CrCl) greater than 50 mL/min, administer 2.5 grams (ceftazidime 2 grams and avibactam 0.5 grams) every 8 hours by IV infusion over 2 hours 1
- For complicated intra-abdominal infections (cIAI), ceftazidime-avibactam should be given concurrently with metronidazole 500 mg IV every 6-8 hours 2, 1
- For complicated urinary tract infections (cUTI) including pyelonephritis, the same dosage of 2.5 grams every 8 hours is recommended 3, 1
- For hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP), the standard dosage of 2.5 grams every 8 hours is also recommended 1
Pediatric Dosing
- For children aged 2 years to less than 18 years with estimated glomerular filtration rate (eGFR) greater than 50 mL/min/1.73 m²: 62.5 mg/kg (ceftazidime 50 mg/kg and avibactam 12.5 mg/kg) up to a maximum of 2.5 grams every 8 hours 1
- For children aged 6 months to less than 2 years: 62.5 mg/kg every 8 hours 1
- For children aged 3 months to less than 6 months: 50 mg/kg (ceftazidime 40 mg/kg and avibactam 10 mg/kg) every 8 hours 1
- For infants greater than 28 days to less than 3 months: 37.5 mg/kg (ceftazidime 30 mg/kg and avibactam 7.5 mg/kg) every 8 hours 1
- For neonates less than or equal to 28 days with gestational age 31 weeks and older: 25 mg/kg (ceftazidime 20 mg/kg and avibactam 5 mg/kg) every 8 hours 1
Dosage Adjustment for Renal Impairment
Renal clearance is the primary elimination pathway for both ceftazidime and avibactam, necessitating dose adjustment in patients with impaired renal function 4:
- For patients with moderate to severe renal impairment, dose adjustment is required as both drugs are primarily eliminated through the kidneys 4
- Specific dosage adjustments should be made based on creatinine clearance values 1
Duration of Treatment
- For complicated intra-abdominal infections: 5-14 days 2, 1
- For complicated urinary tract infections: 7-14 days 2, 1
- For hospital-acquired and ventilator-associated bacterial pneumonia: 7-14 days 1
- For bloodstream infections: 7-14 days 2
Special Considerations
- The fixed-dose combination ratio of ceftazidime to avibactam is 4:1, which aligns with their complementary pharmacokinetic profiles 4
- Both drugs have a half-life of approximately 2 hours, making the every 8-hour dosing interval appropriate 4
- For treatment of carbapenem-resistant Enterobacterales (CRE) infections, ceftazidime-avibactam is recommended as a treatment option 3, 2
- For CRE urinary tract infections specifically, ceftazidime-avibactam 2.5 g IV every 8 hours is recommended 3
Pharmacokinetic/Pharmacodynamic Considerations
- The target pharmacodynamic indices for efficacy are 50% time above MIC for free ceftazidime and 50% time above threshold concentration of 1 mg/L for free avibactam 4
- Recent studies suggest that extended infusion times may optimize treatment efficacy, especially for severe infections 5
- For severe infections in patients with normal renal function or augmented renal clearance, extending the infusion duration to 3-4 hours may be beneficial to achieve higher PK/PD targets 5