What is the difference between cefixime (Cefixime) and cefpodoxime (Cefpodoxime) in treating infections?

Cefixime vs Cefpodoxime: Differences in Treating Infections

Cefpodoxime is superior to cefixime for respiratory infections due to its better activity against Staphylococcus aureus and drug-resistant Streptococcus pneumoniae, while cefixime is preferred for urinary tract and certain sexually transmitted infections due to its higher activity against Enterobacteriaceae. 1, 2

Antimicrobial Spectrum Differences

Cefixime

• Strengths:

  • More active against Enterobacteriaceae than conventional oral cephalosporins 3
  • Effective against Haemophilus influenzae, Streptococcus pyogenes, Streptococcus pneumoniae, and Branhamella catarrhalis 4
  • Resistant to hydrolysis by many beta-lactamases 4

• Limitations:

  • Poor activity against Staphylococcus aureus 4
  • Ineffective against Pseudomonas aeruginosa 4
  • Poor activity against drug-resistant S. pneumoniae (DRSP) 2

Cefpodoxime

• Strengths:
  • Broad spectrum encompassing both Gram-negative and Gram-positive bacteria 5
  • Enhanced antistaphylococcal activity (distinguishing it from cefixime) 5
  • Stable against most commonly found plasmid-mediated beta-lactamases 5
  • Better activity against H. influenzae compared to cefixime 2

Pharmacokinetic Differences

Cefixime

• Elimination half-life: approximately 3 hours 4
• Dosing: Once or twice daily (200-400 mg/day) 4
• Approximately 20% excreted by kidneys as active drug 3

Cefpodoxime

• Administered as prodrug (cefpodoxime proxetil) which is de-esterified by intestinal mucosa 5
• Elimination half-life: 1.9 to 3.7 hours 5
• Dosing: Twice daily administration 5

Clinical Applications

Respiratory Tract Infections

• Cefpodoxime is preferred due to:
  • Better activity against S. aureus 5
  • Efficacy comparable to parenteral ceftriaxone in bronchopneumonia 5
  • Suitable for acute bacterial sinusitis 1, 2

Urinary Tract Infections

• Cefixime is often preferred due to:
  • Higher activity against Enterobacteriaceae 3
  • Good efficacy in uncomplicated UTIs 3

Sexually Transmitted Infections

• Cefixime (400 mg orally) has been a recommended regimen for gonorrhea treatment 1
• Cefpodoxime (200 mg) is less active against N. gonorrhoeae than cefixime 1
  • Cure rates for urogenital and rectal infection: 96.5% (CI = 94.8%--98.9%) 1
  • Poor efficacy in pharyngeal infection: 78.9% (CI = 54.5%--94%) 1

Pediatric Considerations

• Both antibiotics are effective in pediatric infections 6, 4
• Cefpodoxime demonstrates good efficacy in:
  • Acute otitis media
  • Tonsillitis/pharyngitis
  • Lower respiratory tract infections
  • Skin and soft tissue infections 6

Adverse Effects

Cefixime

• Diarrhea and stool changes in up to 20% of patients 7
• Lower incidence of adverse effects with twice daily dosing (200 mg) compared to once daily (400 mg) 3

Cefpodoxime

• Generally well tolerated 5
• Mild to moderate gastrointestinal disturbances in 4-15% of patients 5
• Better taste acceptance compared to other cephalosporins 2
• No high prevalence of serum sickness-like reactions (unlike cefaclor) 1

Clinical Decision-Making Algorithm

1. For respiratory infections:

   • Choose cefpodoxime if S. aureus is suspected or confirmed
   • Choose cefpodoxime for sinusitis when amoxicillin/clavulanate fails or isn't tolerated

2. For urinary tract infections:

   • Choose cefixime for uncomplicated UTIs, especially those caused by Enterobacteriaceae

3. For gonorrhea:

   • Choose cefixime (400 mg) over cefpodoxime, particularly for pharyngeal infections

4. For pediatric infections:

   • Both are suitable, but consider taste acceptance (cefpodoxime may be better tolerated)

5. For patients with GI sensitivity:

   • Consider cefpodoxime due to potentially better GI tolerability
   • If using cefixime, administer as twice daily rather than once daily dosing