What is the recommended dose of meropenem for a patient with impaired renal function (IRF) undergoing dialysis?

Meropenem Dosing for Dialysis Patients

For patients on intermittent hemodialysis (IHD), administer 500 mg every 24 hours with dosing after each dialysis session, as approximately 50% of meropenem is removed during hemodialysis. 1, 2

Dosing Algorithm Based on Dialysis Modality

Intermittent Hemodialysis (IHD)

• The FDA label recommends 500 mg every 24 hours for patients with creatinine clearance <10 mL/min, which includes IHD patients 1
• Administer the dose after dialysis sessions to prevent premature drug removal and ensure adequate exposure, as hemodialysis eliminates approximately 50% of meropenem and shortens the elimination half-life from 7.0 hours to 2.9 hours 3, 2
• The elimination half-life in anuric patients with end-stage renal disease is prolonged up to 13.7 hours off dialysis 4

Continuous Renal Replacement Therapy (CRRT)

• For patients on CRRT, use 1 gram every 8 hours to compensate for continuous drug removal, as CRRT removes 25-50% of meropenem 3, 4
• The elimination half-life during CVVH is approximately 2.5-8.7 hours, significantly shorter than in anuric patients not receiving renal replacement therapy 3
• Peak plasma concentrations after 1 gram dosing during CRRT range from 18-45 mg/L, with trough levels after 6 hours of approximately 6.6 mg/L 4, 5

Sustained Low-Efficiency Dialysis (SLED)

• Maintain the full 1 gram dose every 12 hours for SLED patients to preserve concentration-dependent bactericidal activity 3
• Do not reduce individual doses below 1 gram, as smaller doses may compromise efficacy despite renal impairment 3

Critical Considerations for Specific Clinical Scenarios

Infections with Resistant Organisms

• When treating infections with organisms having MIC ≥4-8 mg/L, use extended 3-hour infusion of 1 gram every 8 hours, even in dialysis patients, to maximize time above MIC 3
• For carbapenem-resistant Enterobacterales with meropenem MIC ≥8 mg/L, extended 3-hour infusion is specifically recommended 3

Continuous Venovenous Hemofiltration (CVVH) Specifics

• CVVH removes 25-50% of meropenem, with hemofiltration clearance of approximately 22 mL/min 4, 6
• The recommended dose is 1 gram every 8 hours, which provides peak concentrations of 28-45 mg/L and trough levels of 6.6-11.9 mg/L 5, 6

Continuous Venovenous Hemodiafiltration (CVVHDF)

• CVVHDF removes 13-53% of meropenem, requiring 1 gram every 8-12 hours 3, 4

Common Pitfalls to Avoid

• Never administer meropenem before IHD sessions, as this leads to premature drug removal and subtherapeutic levels 3
• Do not use the standard renal impairment dosing (500 mg every 24 hours) for patients on CRRT, as continuous removal requires higher doses (1 gram every 8 hours) 3, 5
• Avoid reducing individual doses below 1 gram in SLED patients, as this compromises concentration-dependent killing 3
• Do not assume all forms of renal replacement therapy have equivalent drug removal—CVVH removes significantly more meropenem (25-50%) than CVVHDF (13-53%) 4

Monitoring Recommendations

• Consider therapeutic drug monitoring in critically ill dialysis patients to ensure adequate exposure, particularly when treating resistant organisms 3
• Monitor for neurological toxicity if trough concentrations exceed 64 mg/L 3
• Peak plasma concentrations should reach 38-53 mg/L for adequate antibacterial effect in IHD patients receiving 500 mg 2, 6