Faropenem: Proper Use and Treatment Protocol
Faropenem medoxomil is an oral penem antibiotic indicated for community-acquired respiratory tract infections (acute bacterial sinusitis, acute exacerbations of chronic bronchitis, community-acquired pneumonia) and uncomplicated skin/soft tissue infections, dosed at 300 mg twice daily for 7-10 days. 1, 2
Approved Indications and Dosing
Acute Bacterial Sinusitis
- Standard regimen: 300 mg orally twice daily for 7 days 3, 4
- Seven-day treatment demonstrates equivalent efficacy to 10-day cefuroxime axetil 250 mg twice daily, with clinical cure rates of 80-89% 3, 4
- Ten-day regimens show similar efficacy (81.8% cure rate) but offer no additional benefit over 7-day treatment 4
Acute Exacerbations of Chronic Bronchitis and Community-Acquired Pneumonia
- Dosing: 300 mg orally twice daily for 7-10 days 2
- Demonstrates equivalent efficacy to comparators including clarithromycin, azithromycin, and cefpodoxime 2
Uncomplicated Skin and Soft Tissue Infections
- Dosing: 300 mg orally twice daily for 7-10 days 2
- Particularly effective for animal and human bite infections, with 98% activity against aerobic pathogens and 97% against anaerobic isolates 5
- Excellent activity against Pasteurella species and Eikenella corrodens (MIC ≤0.25 mg/L) 5
Antimicrobial Spectrum
Organisms with Excellent Activity (MIC ≤0.25-1 mg/L)
- Streptococcus pneumoniae (97.3% eradication rate) 3
- Haemophilus influenzae (85-90.5% eradication rate) 3
- Moraxella catarrhalis (83-100% eradication rate) 3
- Staphylococcus aureus (methicillin-susceptible strains, 88.9-90.9% eradication) 3
- Most anaerobes including Bacteroides species 5
Organisms with NO Activity (Avoid Use)
- Methicillin-resistant Staphylococcus aureus (MRSA) 2
- Vancomycin-resistant Enterococcus faecium (VRE) 2
- Pseudomonas aeruginosa 2
- Stenotrophomonas maltophilia 2
Key Advantages Over Comparators
Gastrointestinal Tolerability
- Minimal impact on GI flora results in significantly less diarrhea compared to amoxicillin-clavulanate 1
- Drug-related adverse events occur in only 9.5% of patients (versus 10.3% with cefuroxime) 3
- Most common side effects: diarrhea (2.2%), nausea/vomiting (1.5%), abdominal pain (0.7%), skin reactions (1.5%) 3
Drug Interactions and Dosing Adjustments
- Almost no drug-drug interactions 1
- Minimal dosage adjustments required in typical community-acquired infection populations 1
Critical Prescribing Considerations
When to Choose Faropenem
- Community-acquired respiratory infections in patients requiring oral beta-lactam therapy 1, 2
- Patients with beta-lactam allergy concerns who can tolerate penems 1
- Animal or human bite infections requiring oral therapy 5
- Patients who experienced GI intolerance with amoxicillin-clavulanate 1
When NOT to Use Faropenem
- Suspected or confirmed MRSA infections 2
- Hospital-acquired infections or healthcare-associated pneumonia (not studied in these populations) 2
- Pseudomonas coverage required 2
- Critically ill patients requiring IV therapy (no IV formulation available) 2
Common Pitfalls and How to Avoid Them
Pitfall #1: Using for Inappropriate Pathogens
- Do not prescribe for suspected MRSA, VRE, or Pseudomonas infections 2
- Verify local susceptibility patterns before empiric use 1
Pitfall #2: Incorrect Duration
- For acute bacterial sinusitis, 7 days is sufficient—do not extend unnecessarily to 10 days 4
- Longer courses offer no additional benefit and increase cost and adverse event risk 4
Pitfall #3: Overlooking Resistance Patterns
- Faropenem is resistant to most beta-lactamases including ESBLs and AmpC beta-lactamases 2
- However, always consider local resistance patterns, particularly for S. pneumoniae and H. influenzae 1