Meropenem Dosing for Patients with GFR of 20 mL/min
For patients with a GFR of 20 mL/min, the recommended dose of meropenem is one-half the standard dose (500 mg for skin/skin structure infections or 1 gram for intra-abdominal infections) administered every 12 hours. 1
Dosing Rationale
The FDA-approved drug label for meropenem provides clear guidance for dosing in patients with renal impairment:
| Creatinine Clearance (mL/min) | Dose | Dosing Interval |
|---|---|---|
| Greater than 50 | Recommended dose | Every 8 hours |
| 26 to 50 | Recommended dose | Every 12 hours |
| 10 to 25 | One-half recommended dose | Every 12 hours |
| Less than 10 | One-half recommended dose | Every 24 hours |
With a GFR of 20 mL/min, the patient falls into the 10-25 mL/min category, requiring one-half the recommended dose administered every 12 hours 1.
Practical Application
For skin and skin structure infections:
- Standard dose: 500 mg every 8 hours
- Adjusted dose for GFR 20 mL/min: 250 mg every 12 hours
For intra-abdominal infections:
- Standard dose: 1 gram every 8 hours
- Adjusted dose for GFR 20 mL/min: 500 mg every 12 hours
For infections caused by Pseudomonas aeruginosa:
- Standard dose: 1 gram every 8 hours
- Adjusted dose for GFR 20 mL/min: 500 mg every 12 hours
Administration Considerations
- Meropenem should be administered by intravenous infusion over approximately 15-30 minutes
- Alternatively, doses can be administered as an intravenous bolus injection over approximately 3-5 minutes 1
Important Clinical Considerations
- Meropenem is predominantly excreted unchanged in the urine, making dosage adjustments necessary in patients with renal insufficiency 2
- The half-life of meropenem (approximately 1 hour in healthy volunteers) is prolonged in patients with renal impairment 2
- Underdosing should be avoided due to the risk of treatment failure and development of antimicrobial resistance
- Regular monitoring of renal function is recommended during treatment to assess the need for further dose adjustments
Special Situations
For critically ill patients with acute infections, some research suggests that higher doses may be needed to achieve therapeutic targets, particularly for less susceptible organisms. However, the FDA-approved dosing recommendations should be followed unless there are compelling clinical reasons to deviate 3, 4.
For patients on continuous renal replacement therapy (CRRT), different dosing may be required, but this is not applicable to the current scenario with a GFR of 20 mL/min 3.