What is the dosage of Merrem (Meropenem) for infectious cellulitis?

From the Guidelines

Meropenem (Merrem) for infectious cellulitis is typically dosed at 1 gram intravenously every 8 hours for adults with normal renal function, with the option to increase to 2 grams every 8 hours for severe infections, as recommended in combination with vancomycin for severe nonpurulent cases 1. When considering the treatment of infectious cellulitis, it's crucial to assess the severity and potential causative pathogens. For typical cases without systemic signs of infection, antimicrobial agents active against streptococci are recommended 1. However, for cellulitis with systemic signs of infection or in cases where MRSA is suspected, broader coverage including vancomycin is advised 1.

Key Considerations for Merrem Dosage:

• For adults with normal renal function, the standard dose is 1 gram every 8 hours.
• For severe infections, the dose may be increased to 2 grams every 8 hours.
• Dose adjustments are necessary for patients with renal impairment:
  • Creatinine clearance 26-50 mL/min: 1 gram every 12 hours.
  • Creatinine clearance 10-25 mL/min: 500 mg every 12 hours.
  • Creatinine clearance less than 10 mL/min: 500 mg every 24 hours.

Monitoring and Administration:

• Meropenem should be administered as a slow IV infusion over 15-30 minutes to minimize vein irritation.
• Patients should be monitored for potential side effects, including seizures, especially those with CNS disorders or renal impairment, and allergic reactions. Given the broad-spectrum efficacy of meropenem against both gram-positive and gram-negative bacteria, including MRSA and Pseudomonas, it is an appropriate choice for severe or complicated cellulitis, particularly when polymicrobial infection is suspected or when the patient has failed previous antibiotic therapy 1. The recommended duration of antimicrobial therapy is typically 5 days but may be extended if the infection has not improved within this time period 1.

From the FDA Drug Label

The recommended dose of meropenem for injection is 500 mg given every 8 hours for skin and skin structure infections

• Merrem dosage for infectious cellulitis: The recommended dose is 500 mg every 8 hours for skin and skin structure infections, which includes infectious cellulitis 2.
• Note that when treating complicated skin and skin structure infections caused by P. aeruginosa, a dose of 1 gram every 8 hours is recommended 2.

From the Research

Merrem Dosage for Infectious Cellulitis

• The dosage of Merrem (meropenem) for infectious cellulitis is not explicitly stated in the provided studies, but it is indicated for use in complicated skin and skin structure infections (cSSSI) 3, 4.
• Meropenem has a broad spectrum of in vitro activity against Gram-positive and Gram-negative pathogens, including extended-spectrum beta-lactamase (ESBL)- and AmpC-producing Enterobacteriaceae 3.
• In the treatment of cSSSI, meropenem has shown similar efficacy to comparator antibacterial agents, including imipenem/cilastatin, clindamycin plus tobramycin or gentamicin, and cefotaxime plus metronidazole 3, 4.
• The recommended dosage of meropenem for cSSSI is 500 mg every 8 hours, but higher doses (e.g., 1 g every 8 hours) may be considered for treatment of cSSSI in higher-risk patients where Pseudomonas aeruginosa is a suspected or documented pathogen 4.

Considerations for Treatment

• Antibiotic selection for cellulitis is determined by patient history and risk factors, severity of clinical presentation, and the most likely microbial culprit 5.
• Piperacillin/tazobactam is regarded as a standard treatment for complicated skin and soft tissue infections (cSSTIs) due to its antibiotic spectrum, safety, and clinical efficacy 6.
• Meropenem is an effective and safe alternative for monotherapy when used for appropriate types of cSSTIs, but its dosage and administration should be considered in the context of the individual patient's condition and the suspected or documented pathogen 3, 4.