What is the recommended dose of Ceftazidime (Ceftazidime) for adults with normal renal function and impaired renal function?

Ceftazidime Dosing for Adults

Standard Dosing for Normal Renal Function

For adults with normal renal function, the recommended dose of ceftazidime is 1 gram intravenously every 8 to 12 hours for most infections, with higher doses of 2 grams every 8 hours reserved for severe life-threatening infections, meningitis, and serious intra-abdominal or gynecologic infections. 1

Infection-Specific Dosing (Normal Renal Function)

• Uncomplicated urinary tract infections: 250 mg IV/IM every 12 hours 1
• Complicated urinary tract infections: 500 mg IV/IM every 8 to 12 hours 1
• Uncomplicated pneumonia and mild skin/soft tissue infections: 500 mg to 1 gram IV/IM every 8 hours 1
• Bone and joint infections: 2 grams IV every 12 hours 1
• Serious gynecologic and intra-abdominal infections: 2 grams IV every 8 hours 1
• Meningitis: 2 grams IV every 8 hours 1
• Very severe life-threatening infections (especially in immunocompromised patients): 2 grams IV every 8 hours 1
• Pseudomonas lung infections in cystic fibrosis patients: 30 to 50 mg/kg IV every 8 hours (maximum 6 grams per day) 1

Special Considerations for Severe Infections

• For carbapenem-resistant Pseudomonas aeruginosa susceptible to ceftazidime, use 2 grams IV every 8 hours for 5-14 days (longer courses of 10-14 days for pneumonia and bloodstream infections) 2
• Intravenous ciprofloxacin was found to be more cost-effective compared to IV ceftazidime in patients who had not received quinolone prophylaxis 3

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Dosing for Impaired Renal Function

Ceftazidime is excreted almost exclusively by glomerular filtration, requiring dose reduction in patients with creatinine clearance (CrCl) below 50 mL/min to prevent accumulation and potential neurotoxicity. 1, 4

Initial Loading Dose

• Give 1 gram IV as a loading dose in all patients with suspected renal insufficiency before adjusting to maintenance dosing 1

Maintenance Dosing Based on Creatinine Clearance

The following maintenance regimen should be used after the loading dose 1:

• CrCl 50-31 mL/min: 1 gram every 12 hours
• CrCl 30-16 mL/min: 1 gram every 24 hours
• CrCl 15-6 mL/min: 500 mg every 24 hours
• CrCl <5 mL/min: 500 mg every 48 hours

Important caveat: If the dose recommended for the specific infection type (Table 3 in FDA label) is lower than the renal-adjusted dose above, use the lower dose 1

Alternative Dosing Intervals Based on Research

Research studies support slightly different intervals 4:

• CrCl >50 mL/min: Every 8 hours
• CrCl 30-50 mL/min: Every 12 hours
• CrCl 15-30 mL/min: Every 24 hours
• CrCl <15 mL/min: Every 36-48 hours

Estimating Creatinine Clearance

When only serum creatinine is available, use the Cockcroft-Gault equation 1:

• Males: CrCl (mL/min) = [Weight (kg) × (140 - age)] / [72 × serum creatinine (mg/dL)]
• Females: 0.85 × male value

The serum creatinine must represent steady-state renal function 1

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Dialysis Patients

Hemodialysis

• Loading dose: 1 gram IV 1
• Maintenance: 1 gram after each hemodialysis session 1
• During hemodialysis, the elimination half-life is approximately 4.7 hours, with plasma concentrations reduced by approximately 88% during a 6-8 hour session 5, 6

Peritoneal Dialysis

• Loading dose: 1 gram IV (or 10 mg/kg) 1, 7
• Maintenance: 500 mg every 24 hours 1
• Alternative: Ceftazidime can be incorporated directly into dialysis fluid at 250 mg per 2 liters of dialysis fluid 1
• For chronic peritoneal dialysis, continuous administration of 5 mg/kg into each dialysis cavity after the loading dose 7

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Critical Dosing Considerations

Severe Infections in Renal Impairment

• In patients with severe infections who would normally receive 6 grams daily but have renal insufficiency, the unit dose may be increased by 50% or the dosing frequency may be increased appropriately 1
• Further dosing should be determined by therapeutic monitoring, severity of infection, and pathogen susceptibility 1

Pharmacokinetic Changes in Renal Failure

• The elimination half-life increases from approximately 1.5-2 hours in normal renal function to up to 25-45 hours in severe renal impairment 5, 6
• The volume of distribution and protein binding remain relatively unchanged across different levels of renal function 5, 6
• Renal clearance of ceftazidime correlates directly with creatinine clearance 5, 4

Monitoring and Safety

• Monitor for neurotoxicity (seizures, encephalopathy, confusion), particularly in patients with renal impairment where drug accumulation can occur 8
• Continue therapy for 2 days after signs and symptoms resolve, though complicated infections may require longer treatment 1
• Pediatric patients with renal insufficiency require creatinine clearance adjusted for body surface area or lean body mass 1

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Common Pitfalls to Avoid

• Do not skip the loading dose in renal impairment—this delays achievement of therapeutic concentrations 1
• Avoid intra-arterial administration 1
• Do not use standard dosing intervals in patients with CrCl <50 mL/min without adjustment, as this leads to drug accumulation and increased neurotoxicity risk 8, 4
• Remember to give supplemental doses after hemodialysis—ceftazidime is significantly removed during dialysis 1, 6