What is the recommended dose of cefepime for pneumonia?

Cefepime Dosing for Pneumonia

For adults with moderate to severe pneumonia, administer cefepime 1-2 g intravenously every 8-12 hours, with the higher dose (2 g every 8 hours) reserved for Pseudomonas aeruginosa coverage. 1

Adult Dosing

Standard Regimens

• Moderate to severe pneumonia: 1-2 g IV every 8-12 hours for 10 days 1
• Pneumonia with suspected Pseudomonas aeruginosa: 2 g IV every 8 hours 1
• Administer each dose as an intravenous infusion over approximately 30 minutes 1

Dosing Adjustments for Renal Impairment

Cefepime requires dose adjustment based on creatinine clearance (CrCL), as it is renally eliminated 1:

• CrCL 30-60 mL/min: 2 g every 24 hours (for standard 2 g every 12-hour regimen) or 2 g every 12 hours (for 2 g every 8-hour regimen) 1
• CrCL 11-29 mL/min: 1 g every 24 hours (for standard regimen) or 2 g every 24 hours (for intensive regimen) 1
• CrCL <11 mL/min: 500 mg every 24 hours (for standard regimen) or 1 g every 24 hours (for intensive regimen) 1
• Hemodialysis patients: 1 g on day 1, then 500 mg every 24 hours thereafter, administered after dialysis on dialysis days 1

Critical caveat: Even with dose adjustment for renal impairment (CrCL <30 mL/min), cefepime accumulation can occur, leading to neurotoxicity manifesting as confusion, muscle jerks, or non-convulsive seizures 2. Plasma level monitoring should be considered in patients with significant renal dysfunction 2.

Pediatric Dosing (2 months to 16 years)

• Standard pneumonia: 50 mg/kg per dose IV every 12 hours, not to exceed adult dosing 1
• Moderate to severe pneumonia with Pseudomonas aeruginosa: 50 mg/kg per dose IV every 8 hours 1
• Maximum dose should not exceed the recommended adult dose 1

Pharmacokinetic/Pharmacodynamic Considerations

Efficacy Targets

• Cefepime achieves optimal bactericidal activity when free drug concentrations remain above the MIC for ≥50% of the dosing interval (T>MIC ≥50%) 2
• The standard 2 g every 12-hour regimen provides adequate coverage for pathogens with MIC ≤4 mg/L in 100% of patients 2
• Important limitation: Only 45-65% of patients achieve adequate coverage for pathogens with MIC ≥8 mg/L (upper limit of susceptibility) with standard dosing 2

Alternative Dosing for Critically Ill Patients

• For ventilator-associated pneumonia or critically ill patients, consider 2 g every 8 hours as a 3-hour prolonged infusion to optimize pharmacodynamic targets 3
• This regimen achieves T>MIC ≥50% in 91.8% of patients for MIC 8 mg/L, 78.1% for MIC 16 mg/L, and 50.3% for MIC 32 mg/L 3

Clinical Efficacy Evidence

Cefepime monotherapy demonstrates comparable efficacy to third-generation cephalosporins (ceftriaxone, ceftazidime, cefotaxime) for community-acquired and nosocomial pneumonia 4, 5. Clinical response rates of 80-85% have been documented in hospitalized patients with moderate to severe pneumonia 5. Importantly, cefepime maintains activity against Enterobacteriaceae resistant to third-generation cephalosporins due to its stability against AmpC beta-lactamases 4.

Important Clinical Considerations

When Cefepime May Not Be First-Line

• Pediatric community-acquired pneumonia: Guidelines prioritize ampicillin (150-200 mg/kg/day) or ceftriaxone (50-100 mg/kg/day) over cefepime for hospitalized children 6
• Atypical pathogen coverage: Cefepime lacks activity against Mycoplasma pneumoniae and Chlamydophila pneumoniae; add a macrolide if these pathogens are suspected 6
• MRSA coverage: Add vancomycin (40-60 mg/kg/day) or clindamycin if Staphylococcus aureus is suspected based on clinical characteristics 6

Safety Profile

• Generally well tolerated with adverse events similar to other cephalosporins 4
• Most common adverse events: rash, diarrhea, nausea, vomiting 4
• Neurotoxicity risk: Particularly in renal impairment, manifesting as confusion, seizures, or encephalopathy 2