From the Guidelines
Levofloxacin does cover Pseudomonas aeruginosa, but it is considered to have moderate activity against this organism and is often recommended as part of combination therapy for serious infections. Levofloxacin is a fluoroquinolone antibiotic typically dosed at 500-750 mg once daily for most infections. For Pseudomonas infections, the higher dose of 750 mg daily is generally preferred to optimize efficacy, as suggested by guidelines from the Infectious Diseases Society of America and the American Thoracic Society 1. However, it's essential to note that resistance rates to fluoroquinolones among Pseudomonas isolates have been increasing in many regions, which may impact the effectiveness of levofloxacin as a monotherapy for serious Pseudomonas infections.
Some key points to consider when using levofloxacin for Pseudomonas infections include:
- The mechanism of action involves inhibition of bacterial DNA gyrase and topoisomerase IV, disrupting DNA replication.
- Local antibiogram data should guide therapy decisions, as susceptibility patterns vary significantly by region and institution 1.
- For critically ill patients with suspected Pseudomonas infections, empiric coverage often includes more reliable antipseudomonal agents until susceptibility results are available.
- Combination therapy with another antipseudomonal agent, such as an aminoglycoside or beta-lactam, may be recommended for serious Pseudomonas infections to improve outcomes and reduce the risk of resistance development, as supported by guidelines from the European Respiratory Society, European Society of Intensive Care Medicine, European Society of Clinical Microbiology and Infectious Diseases, and Asociación Latinoamericana del Tórax 1.
In terms of specific recommendations, the most recent and highest-quality study suggests that levofloxacin can be used as part of combination therapy for Pseudomonas infections, but the choice of antibiotic should be based on the results of antimicrobial susceptibility testing and local epidemiology 1. The use of levofloxacin as monotherapy for serious Pseudomonas infections is not generally recommended, and combination therapy with another antipseudomonal agent is often preferred to optimize outcomes and reduce the risk of resistance development.
From the FDA Drug Label
Levofloxacin tablets are indicated for the treatment of nosocomial pneumonia due to methicillin-susceptible Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Escherichia coli, Klebsiella pneumoniae, Haemophilus influenzae, or Streptococcus pneumoniae. Where Pseudomonas aeruginosa is a documented or presumptive pathogen, combination therapy with an anti-pseudomonal β-lactam is recommended [see Clinical Studies (14.1)]. Levofloxacin tablets are indicated for the treatment of complicated urinary tract infections (mild to moderate) due to Enterococcus faecalis, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, or Pseudomonas aeruginosa
Levofloxacin has coverage for Pseudomonas aeruginosa, but combination therapy with an anti-pseudomonal β-lactam is recommended when Pseudomonas aeruginosa is a documented or presumptive pathogen. 2
From the Research
Levofloxacin Coverage of Pseudomonas
- Levofloxacin has been studied for its effectiveness against Pseudomonas aeruginosa in several studies 3, 4, 5, 6.
- The in vitro activity of levofloxacin against P. aeruginosa has been documented, with studies showing that it is as active as ciprofloxacin against this pathogen 4.
- Levofloxacin has been shown to be effective in combination with other agents, such as ceftazidime, cefepime, imipenem, piperacillin-tazobactam, and amikacin, against P. aeruginosa 3, 5.
- The pharmacodynamic properties of levofloxacin allow for the treatment of pseudomonal infections, and clinical results have documented its efficacy in treating infections sustained by P. aeruginosa 6.
- However, it is worth noting that the optimal antibiotic regimen for P. aeruginosa bacteremia is still controversial, and other antibiotics such as ceftazidime, carbapenems, and piperacillin-tazobactam may also be effective as single definitive therapy 7.
Key Findings
- Levofloxacin 750 mg/day in combination with another agent active against P. aeruginosa may be clinically beneficial and superior to combinations using lower doses of levofloxacin 3.
- Levofloxacin shows excellent bactericidal activity against P. aeruginosa, and its MIC values do not show any statistical difference using two different inocula 4.
- Combinations of fluoroquinolones with beta-lactams or amikacin show enhanced activity against P. aeruginosa and Acinetobacter spp. 5.
- Levofloxacin clinical results extrapolated from published studies document the efficacy of levofloxacin in the treatment of infections sustained by P. aeruginosa 6.