Cefixime and Cefuroxime Coverage
Direct Comparison of Antimicrobial Coverage
Both cefixime and cefuroxime provide comparable coverage against common respiratory pathogens, with cefixime offering superior activity against H. influenzae and M. catarrhalis but inferior coverage against S. pneumoniae, while cefuroxime provides more balanced gram-positive coverage including better staphylococcal activity. 1
Respiratory Tract Infections
Predicted Clinical Efficacy
- In acute bacterial rhinosinusitis, both agents achieve 83-88% predicted clinical efficacy in adults and 82-87% in children, placing them in the same therapeutic tier 1
- This efficacy is based on mathematical modeling accounting for pathogen distribution, spontaneous resolution rates, and in vitro activity 1
Pathogen-Specific Coverage
Cefixime:
- Particularly active against H. influenzae (including beta-lactamase producing strains) and M. catarrhalis 1, 2, 3
- Important limitation: Efficacy predictions are based specifically on H. influenzae and M. catarrhalis coverage only, with weaker S. pneumoniae activity 1
- In otitis media trials, cefixime showed approximately 10% lower response rates against S. pneumoniae compared to controls (69-82% vs 82%) 2
- Demonstrates 71-77% eradication of H. influenzae (both beta-lactamase positive and negative strains) 2
- Shows 84% eradication of M. catarrhalis 2
Cefuroxime:
- Provides more balanced coverage with superior activity against S. pneumoniae and S. pyogenes 1, 4
- Most active cephalosporin against H. influenzae, particularly beta-lactamase producing strains 5
- Active against methicillin-sensitive S. aureus, which cefixime lacks 6, 4
- Covers enterobacteria including E. coli, K. pneumoniae, and P. mirabilis 6, 4
Clinical Application by Infection Type
Acute Bronchiolitis (Children)
- Cefuroxime axetil is specifically recommended when antibiotic therapy is indicated (high fever >38.5°C persisting >3 days, purulent otitis media, or confirmed pneumonia) 1
- Cefixime is not mentioned in this indication 1
Community-Acquired Pneumonia (Children)
- For children <3 years: Neither agent is first-line; amoxicillin 80-100 mg/kg/day is the reference treatment for pneumococcal pneumonia 1
- Cefuroxime is considered redundant to ceftriaxone, which offers broader gram-negative coverage 1
- Second and third generation cephalosporins (except cefixime) may be justified only with inadequate H. influenzae type b vaccination or concurrent purulent otitis media 1
COPD Exacerbations
- Cefuroxime is specifically recommended for moderate-severe COPD without P. aeruginosa risk factors (parenteral: second or third generation cephalosporin including cefuroxime) 1
- Cefixime is not mentioned in COPD guidelines 1
Intra-Abdominal Infections
- Neither agent is recommended as first-line therapy 1
- Cefuroxime was considered redundant because ceftriaxone offers broader gram-negative coverage 1
Gonococcal Infections
Cefixime
- CDC recommends cefixime 400 mg single dose with 97.4% cure rate for uncomplicated urogenital and anorectal gonorrhea 7, 8
- Achieves 91% efficacy for pharyngeal gonorrhea (less robust than urogenital sites) 8
- Critical limitation: Does not provide sustained bactericidal levels comparable to ceftriaxone (maintains free drug concentrations above MIC90 for only 22-50 hours vs longer with ceftriaxone) 8
- Must be combined with azithromycin or doxycycline as it does not treat concurrent chlamydial infection (present in ≥50% of co-infected patients) 8
- Oral administration eliminates injection requirement, improving patient acceptance 8
Cefuroxime
- Not recommended for gonorrhea treatment in current guidelines 7, 8
- Historically active against gonococci including beta-lactamase producing N. gonorrhoeae, but not included in contemporary treatment algorithms 5
Pharmacokinetic Considerations
Cefixime:
- Elimination half-life: ~3 hours, permitting once or twice daily dosing 3, 9
- Absolute bioavailability: Not specified in FDA label but clinically effective orally 2
- Poor activity against S. aureus, enterococci, Listeria, and Pseudomonas 2, 9
Cefuroxime:
- Elimination half-life: ~80 minutes (requires more frequent dosing) 6
- Absolute bioavailability: 68% (oral formulation) 4
- Protein binding: 33% (oral) to 50% (parenteral) 6, 4
- Achieves therapeutic concentrations in pleural fluid, joint fluid, bile, sputum, bone, and CSF 6
- ~89% excreted unchanged by kidneys over 8 hours 6
Key Clinical Caveats
When to Choose Cefixime:
- Uncomplicated gonorrhea when oral therapy preferred and ceftriaxone not feasible 7, 8
- Otitis media or sinusitis when H. influenzae or M. catarrhalis are primary concerns and once-daily dosing improves compliance 1, 2
- Avoid in suspected pneumococcal pneumonia due to inferior S. pneumoniae coverage 1, 2
When to Choose Cefuroxime:
- Pneumococcal infections or when broader gram-positive coverage needed 1, 4
- COPD exacerbations requiring hospitalization 1
- Skin and soft tissue infections requiring staphylococcal coverage 4
- When parenteral therapy needed (cefuroxime available IV/IM; cefixime is oral only) 6
Shared Limitations:
- Neither agent covers Pseudomonas aeruginosa 2, 9
- Neither covers enterococci or MRSA 2, 9
- Both have limited anaerobic coverage (no B. fragilis activity) 5
- Resistance surveillance is critical as cephalosporin resistance patterns evolve 8