Meropenem Dosing for Creatinine Clearance of 60 mL/min
For a 78-year-old male with a creatinine clearance of 60 mL/min, administer meropenem at the standard recommended dose (500 mg every 8 hours for complicated skin/skin structure infections or 1 gram every 8 hours for intra-abdominal infections) without dose reduction. 1
FDA-Approved Dosing Algorithm by Renal Function
The FDA label provides clear guidance based on creatinine clearance thresholds 1:
- CrCl >50 mL/min: Standard dosing (500 mg or 1 gram every 8 hours depending on infection type) 1
- CrCl 26-50 mL/min: Standard dose every 12 hours 1
- CrCl 10-25 mL/min: Half the standard dose every 12 hours 1
- CrCl <10 mL/min: Half the standard dose every 24 hours 1
Since your patient has a CrCl of 60 mL/min, this falls into the ">50 mL/min" category requiring no dose adjustment 1.
Infection-Specific Dosing Considerations
For complicated skin/skin structure infections: 500 mg IV every 8 hours is appropriate, but if Pseudomonas aeruginosa is suspected or confirmed, increase to 1 gram every 8 hours 1.
For intra-abdominal infections: 1 gram IV every 8 hours is the standard dose 1.
Administration: Give as IV infusion over 15-30 minutes, or as IV bolus (for 1 gram doses) over 3-5 minutes 1.
Critical Pitfall: Augmented Renal Clearance Risk
Important caveat: While FDA dosing suggests no adjustment at CrCl 60 mL/min, recent research demonstrates that critically ill patients with CrCl 60-90 mL/min may require higher doses (up to 6 g/day) to achieve adequate pharmacokinetic targets for pathogens at the susceptibility breakpoint (MIC 2 mg/L) 2. However, this patient's CrCl of 60 mL/min is at the lower end of this range, making standard dosing more likely to be adequate 2.
For patients with CrCl ≥90 mL/min (augmented renal clearance), standard dosing is often insufficient and requires either increased dose/frequency or continuous infusion 2. This does not apply to your patient.
Monitoring Recommendations
- Renal function: Monitor creatinine clearance regularly, as changes will necessitate dose adjustments 1
- Clinical response: Assess for therapeutic efficacy within 48-72 hours 1
- CNS effects: Be vigilant for seizures, particularly if the patient has CNS disorders or if renal function deteriorates 1
- Thrombocytopenia: Monitor platelet counts in patients with renal dysfunction 1
Age-Related Consideration
At 78 years old, this patient likely has age-related decline in renal function beyond what creatinine alone suggests 3. The Cockcroft-Gault equation (which factors in age and weight) provides a more accurate estimate than serum creatinine alone for dosing decisions 1.