Does Augmentin (amoxicillin-clavulanate) have anti-pseudomonal action?

Augmentin Does Not Have Anti-Pseudomonal Action

Augmentin (amoxicillin-clavulanate) does not have activity against Pseudomonas aeruginosa and should not be used for treating pseudomonal infections. 1, 2

Evidence on Augmentin's Lack of Anti-Pseudomonal Activity

• Studies have demonstrated that 88% of all Pseudomonas aeruginosa strains are resistant to Augmentin, placing them firmly in the "resistant" category 1
• Research has conclusively shown that Pseudomonas aeruginosa is never susceptible to Augmentin 2
• When considering treatment options for infections potentially caused by P. aeruginosa, guidelines consistently exclude amoxicillin-clavulanate from recommended regimens 3

Antibiotics with Anti-Pseudomonal Activity

For infections where P. aeruginosa is a concern, the following antibiotics are recommended instead:

• Anti-pseudomonal beta-lactams:

  • Piperacillin-tazobactam 3
  • Ceftazidime 3
  • Cefepime 3
  • Carbapenems (imipenem, meropenem) 3

• Fluoroquinolones with anti-pseudomonal activity:

  • Ciprofloxacin (the best oral anti-pseudomonal agent) 3
  • Levofloxacin (at higher doses) 3

• Other anti-pseudomonal agents:

  • Aminoglycosides (amikacin, tobramycin) 3, 4
  • Aztreonam (in patients with beta-lactam allergies) 3

Clinical Implications

• Using Augmentin for suspected pseudomonal infections would lead to treatment failure and potentially worse clinical outcomes 5
• For respiratory tract infections where P. aeruginosa is a concern (such as in bronchiectasis), guidelines specifically recommend alternatives like ciprofloxacin rather than amoxicillin-clavulanate 3
• In intra-abdominal infections where P. aeruginosa might be present, piperacillin-tazobactam is recommended instead of amoxicillin-clavulanate 3
• For febrile neutropenia where P. aeruginosa is a concern, anti-pseudomonal beta-lactams like cefepime, piperacillin-tazobactam, or carbapenems are recommended 3

Risk Factors for Pseudomonal Infections

When deciding on empiric antibiotic therapy, consider these risk factors for P. aeruginosa infection:

• Structural lung disease (e.g., bronchiectasis, cystic fibrosis) 3
• Recent hospitalization, especially ICU stays 3
• Recent antibiotic therapy 3
• Immunocompromised status 3
• Severe illness requiring ICU admission 3

Common Pitfalls to Avoid

• Pitfall #1: Using Augmentin empirically when P. aeruginosa is a possible pathogen, which would lead to treatment failure 1, 2
• Pitfall #2: Assuming that because Augmentin has activity against some beta-lactamase-producing organisms, it will work against P. aeruginosa (it does not) 1
• Pitfall #3: Failing to obtain appropriate cultures before starting empiric therapy when P. aeruginosa is suspected 3
• Pitfall #4: Not recognizing risk factors for P. aeruginosa infection, which would necessitate specific anti-pseudomonal coverage 3