What is the recommended dosage of meropenem (Intravenous IV) for the treatment of intra-abdominal infections (IAI) in adults with normal renal function?

Meropenem Dosage for Intra-Abdominal Infections

The recommended dosage of meropenem for intra-abdominal infections in adults with normal renal function is 1 gram intravenously every 8 hours. 1, 2

Dosing Regimen Details

Adult Patients

• Standard dose: 1 gram IV every 8 hours 1, 2
• Administration method:
  • Intravenous infusion over 15-30 minutes, or
  • Intravenous bolus injection over 3-5 minutes 2
• Duration: 5-7 days if adequate source control is achieved 1

Renal Impairment Adjustments

• CrCl >50 mL/min: 1 gram every 8 hours
• CrCl 26-50 mL/min: 1 gram every 12 hours
• CrCl 10-25 mL/min: 0.5 gram every 12 hours
• CrCl <10 mL/min: 0.5 gram every 24 hours 2

Clinical Context for Use

Meropenem is particularly indicated in the following scenarios:

1. Critically ill patients with intra-abdominal infections 1
2. Patients at risk for infection with ESBL-producing Enterobacteriaceae 1
3. Healthcare-associated infections where multi-drug resistant organisms are a concern 1

Efficacy and Pharmacokinetics

Meropenem demonstrates excellent penetration into peritoneal fluid, with concentrations similar to plasma levels within 1 hour after administration 3. This favorable penetration makes it highly effective for intra-abdominal infections, with clinical response rates of 91-96% reported in clinical studies 4.

The pharmacokinetic profile in patients with intra-abdominal infections shows:

• Peak plasma concentration: 47.58 ± 17.59 μg/mL
• Half-life: 1.04 ± 0.19 hours
• Total plasma clearance: 315.40 ± 71.94 mL/min 5

Alternative Regimens

For patients who cannot receive meropenem, alternative regimens include:

• Doripenem 500 mg IV every 8 hours
• Imipenem/cilastatin 1 gram IV every 8 hours
• Piperacillin/tazobactam 4.5 grams IV every 6 hours 1

Important Clinical Considerations

• Source control remains the cornerstone of treatment for intra-abdominal infections and should be performed urgently 1
• For complicated intra-abdominal infections caused by carbapenem-resistant Enterobacterales, consider ceftazidime-avibactam 2.5 g IV every 8 hours plus metronidazole 500 mg every 6 hours 1
• Duration of therapy should typically be limited to 5-7 days if adequate source control is achieved 1

Common Pitfalls to Avoid

1. Underdosing in critically ill patients - maintain the full 1 gram every 8 hours dosing in these patients unless renal impairment requires adjustment
2. Failure to adjust dose in renal impairment - meropenem is primarily excreted unchanged in urine, making dose adjustments essential 6
3. Prolonged therapy beyond 7 days without clear indication - this increases risk of resistance development and C. difficile infection 7
4. Overlooking source control - antibiotic therapy alone is insufficient without adequate surgical drainage or debridement of infected tissue 1

Remember that meropenem monotherapy has been shown to be as effective as combination therapy (e.g., cefotaxime plus metronidazole) for intra-abdominal infections, simplifying the treatment regimen 4.