From the Guidelines
For gram-negative wound infections, effective oral antibiotic options include fluoroquinolones, such as ciprofloxacin 500-750mg twice daily or levofloxacin 500-750mg once daily, as recommended by the Infectious Diseases Society of America guidelines 1.
Key Considerations
- The choice of antibiotic should be guided by local resistance patterns, patient allergies, and, when available, culture results.
- Treatment duration typically ranges from 7-14 days depending on infection severity and clinical response.
- Ciprofloxacin is particularly effective against Pseudomonas aeruginosa, while trimethoprim-sulfamethoxazole works well for MRSA with gram-negative coverage.
- These medications work by inhibiting bacterial DNA synthesis (fluoroquinolones), blocking folic acid synthesis (trimethoprim-sulfamethoxazole), or inhibiting cell wall synthesis (amoxicillin-clavulanate).
Additional Options
- Amoxicillin-clavulanate (875/125mg twice daily) is also an effective option for gram-negative wound infections.
- The 2021 WHO Essential Medicines List recommends amoxicillin-clavulanate, cloxacillin, and cefalexin as first-choice antibiotics for skin and soft tissue infections, including those caused by gram-negative bacteria 1.
Important Notes
- Adequate wound care with regular cleaning and debridement remains essential alongside antibiotic therapy.
- Patients should be monitored for clinical improvement within 48-72 hours, and therapy should be adjusted if there's inadequate response.
- The Infectious Diseases Society of America guidelines also recommend considering the severity of the infection, the likely etiologic agent(s), and the patient's prior history of antibiotic use when selecting an empiric antibiotic regimen 1.
From the FDA Drug Label
Levofloxacin has in vitro activity against Gram-negative and Gram-positive bacteria fections as described in Indications and Usage (1): Gram-Negative Bacteria Enterobacter cloacae Escherichia coli Haemophilus influenzae Haemophilus parainfluenzae Klebsiella pneumoniae Legionella pneumophila Moraxella catarrhalis Proteus mirabilis Pseudomonas aeruginosa Serratia marcescens
Oral options for gram-negative wound infections include:
- Levofloxacin (PO), which has in vitro activity against various gram-negative bacteria, including:
- Enterobacter cloacae
- Escherichia coli
- Haemophilus influenzae
- Haemophilus parainfluenzae
- Klebsiella pneumoniae
- Legionella pneumophila
- Moraxella catarrhalis
- Proteus mirabilis
- Pseudomonas aeruginosa
- Serratia marcescens 2
From the Research
Oral Options for Gram-Negative Wound Infections
- Levofloxacin is an effective oral option for the treatment of gram-negative infections, including wound infections, as demonstrated by its broad range of activity against Gram-positive and -negative organisms and anaerobes 3.
- Ciprofloxacin is another oral quinolone that can be used to treat infections with gram-negative pathogens, including wound infections, and is recommended as first-line treatment for certain infections such as complicated urinary tract infections and selected pneumonia cases 4.
- Other oral options for gram-negative infections include moxifloxacin, gatifloxacin, and azithromycin, although their effectiveness may vary depending on the specific infection and patient population 3, 4.
- New antimicrobial treatment options are being developed for severe Gram-negative infections, including β-lactam/β-lactamase inhibitor combinations, eravacycline, plazomicin, and cefiderocol, which may provide additional oral options for the treatment of gram-negative wound infections in the future 5.
Considerations for Treatment
- The optimal duration of antibiotic therapy for gram-negative infections depends on many factors, including the severity of the infection, the presence of comorbidities, and the patient's response to treatment, but short-course antibiotic therapy (7 days or less) may be sufficient for many infections 6.
- The choice of antibiotic should be based on factors such as efficacy, side effects, and cost, as well as the potential for resistance development 3, 4.
- Antibiotic stewardship programs can help optimize the use of antibiotics and minimize the development of resistance by promoting appropriate use and dosing of antibiotics 7.