Cefepime Dosing for GFR 59 mL/min with Serious Infection
For a patient with GFR 59 mL/min requiring cefepime for a serious infection, administer 2 g IV every 12 hours for moderate-to-severe pneumonia or complicated intra-abdominal infections, or 2 g IV every 24 hours for severe urinary tract infections, as this GFR falls within the 30-60 mL/min range requiring dose reduction from standard regimens. 1
Dose Adjustment Based on Renal Function
Your patient's GFR of 59 mL/min places them in the 30-60 mL/min creatinine clearance category, which mandates dose adjustment from standard regimens 1:
Standard Dosing by Infection Type (GFR 30-60 mL/min):
Moderate-to-severe pneumonia (including Pseudomonas aeruginosa): 2 g IV every 12 hours (reduced from every 8 hours) 1
Severe urinary tract infections: 2 g IV every 24 hours (reduced from every 12 hours) 1
Complicated skin/skin structure infections: 2 g IV every 24 hours (reduced from every 12 hours) 1
Complicated intra-abdominal infections (with metronidazole): 2 g IV every 12 hours (reduced from every 8-12 hours) 1
Febrile neutropenia: 2 g IV every 12 hours (reduced from every 8 hours) 1
The FDA label explicitly states that patients with creatinine clearance 30-60 mL/min require these adjusted maintenance schedules to compensate for slower renal elimination 1.
Critical Monitoring Requirements
Monitor for neurotoxicity vigilantly, as cefepime-induced encephalopathy occurs even with appropriate renal dosing 2, 3:
Daily mental status assessments are essential, as altered mental status occurs in 92% of cefepime-associated neurotoxicity cases 4
Watch specifically for confusion, muscle jerks, delirium, or inability to tolerate oral intake 2, 5
The severity of renal impairment correlates with neurotoxicity risk—mean GFR in patients developing encephalopathy was 17.20 mL/min versus 32.59 mL/min in those without (p=0.025) 6
Your patient at GFR 59 mL/min has lower risk than those with severe impairment, but vigilance remains necessary 6
Pharmacokinetic Considerations at This GFR Level
Plasma concentrations vary dramatically between individuals (2-3 fold at peak, up to 40-fold at trough), making clinical monitoring more important than assuming dose adjustment alone is sufficient 5:
At GFR 59 mL/min, 100% of patients achieve appropriate coverage (T>MIC ≥50%) for pathogens with MIC ≤4 mg/L 5
However, only 45-65% achieve adequate coverage for pathogens with MIC ≥8 mg/L, which represents the upper susceptibility limit for organisms like Pseudomonas aeruginosa and Enterobacteriaceae 5
If treating suspected resistant organisms, consider obtaining cefepime levels or infectious disease consultation 5
Administration Details
Administer intravenously over approximately 30 minutes 1:
The initial dose should match the maintenance dose (no loading dose reduction needed) 1
Administer at the same time each day to maintain consistent drug levels 1
Duration depends on infection type: 7-10 days for most serious infections 1
Common Pitfall to Avoid
Do not assume that dose adjustment for renal function completely eliminates neurotoxicity risk—two patients in one study with CLCr <30 mL/min developed non-convulsive epilepsy symptoms despite appropriate dose adjustment, with trough concentrations reaching 20-30 mg/L 5. While your patient's GFR of 59 mL/min places them at lower risk, accumulation can still occur, particularly if renal function deteriorates during treatment 2, 5.