Does meropenem cover Pseudomonas aeruginosa?

From the Guidelines

Yes, meropenem is effective against Pseudomonas aeruginosa infections, as it is a broad-spectrum carbapenem antibiotic with antipseudomonal activity. According to the Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults 1, meropenem is recommended as an option for treating Pseudomonas infections, particularly in patients admitted to the ICU. The guidelines suggest using an antipneumococcal, antipseudomonal β-lactam (such as piperacillin-tazobactam, cefepime, imipenem, or meropenem) plus either ciprofloxacin or levofloxacin, or the above β-lactam plus an aminoglycoside and azithromycin, for Pseudomonas infection.

Key points to consider when using meropenem for Pseudomonas infections include:

• The typical adult dosage for serious Pseudomonas infections is 1 gram administered intravenously every 8 hours, with adjustments needed for patients with renal impairment 1.
• Meropenem works by inhibiting bacterial cell wall synthesis by binding to penicillin-binding proteins, causing bacterial cell death.
• Meropenem penetrates well into most body tissues and fluids, including the cerebrospinal fluid, making it useful for various infection sites.
• However, resistance can develop through mechanisms like efflux pumps, altered membrane permeability, or carbapenemase production, so susceptibility testing is important before initiating therapy 1.
• In some cases, combination therapy with another anti-pseudomonal agent may be considered for severe infections to prevent resistance development.

It is essential to note that the guidelines recommend combination therapy for Pseudomonas infections to prevent inappropriate initial therapy and to ensure coverage for other potential pathogens 1. Meropenem is a suitable option for treating Pseudomonas aeruginosa infections, but its use should be guided by susceptibility testing and clinical judgment.

From the FDA Drug Label

Meropenem for injection is indicated for the treatment of complicated skin and skin structure infections (cSSSI) due to ... Pseudomonas aeruginosa, ... Meropenem for injection is indicated for the treatment of complicated appendicitis and peritonitis caused by ... Pseudomonas aeruginosa, ...

Yes, meropenem covers Pseudomonas aeruginosa 2.

• The drug label explicitly lists Pseudomonas aeruginosa as one of the microorganisms that meropenem is effective against.
• The recommended dose for treating complicated skin and skin structure infections caused by P. aeruginosa is 1 gram every 8 hours.

From the Research

Meropenem Coverage Against Pseudomonas

• Meropenem has been shown to be effective against Pseudomonas aeruginosa in various studies 3, 4, 5, 6, 7.
• The antibiotic has been found to be bactericidal against susceptible P. aeruginosa isolates, with extended infusion regimens offering improved efficacy compared to intermittent bolus administration 4.
• Meropenem has also been shown to be effective against meropenem-resistant P. aeruginosa isolates when used in combination with other antibiotics, such as amikacin or colistin 3, 4.
• The optimal meropenem concentrations to treat multidrug-resistant P. aeruginosa septic shock have been found to be at least 40% of the time between two administrations in which drug levels were four times higher than the MIC of the pathogen 7.

Factors Affecting Meropenem Efficacy

• The minimum inhibitory concentration (MIC) of meropenem has been found to be an important factor in determining its efficacy against P. aeruginosa 5, 7.
• The use of meropenem in combination with other antibiotics, such as ceftazidime or colistin, has been shown to be more effective than monotherapy in reducing viable cell numbers and limiting the development of resistance 3, 4, 6.
• The mode of administration, including extended infusion or intermittent bolus, can also impact the efficacy of meropenem against P. aeruginosa 4.

Clinical Implications

• Meropenem can be an effective treatment option for P. aeruginosa infections, particularly when used in combination with other antibiotics or optimized to achieve high concentrations 3, 4, 7.
• Clinicians should consider using meropenem in combination with other antibiotics, such as amikacin or colistin, for the initial management of P. aeruginosa infections, and adjust the regimen based on antibiotic susceptibility results 3.
• High meropenem dosages, such as 12 g/day, may be necessary to achieve optimal concentrations and cure multidrug-resistant P. aeruginosa septic shock 7.