What is the difference between Augmentin (amoxicillin-clavulanate) and amoxicillin for the treatment of otitis media (OM)?

Augmentin vs Amoxicillin for Otitis Media Treatment

High-dose amoxicillin should be used as first-line treatment for most cases of acute otitis media (AOM), while Augmentin (amoxicillin-clavulanate) should be reserved for specific situations where beta-lactamase-producing organisms are likely present. 1

Key Differences Between Augmentin and Amoxicillin

Antimicrobial Coverage

• Amoxicillin:

  • Effective against susceptible and intermediately resistant Streptococcus pneumoniae (83-87% of isolates)
  • Limited activity against beta-lactamase-producing organisms
  • Recommended dosage: 80-90 mg/kg/day in 2 divided doses 1

• Augmentin (amoxicillin-clavulanate):

  • Contains clavulanic acid, a beta-lactamase inhibitor
  • Effective against S. pneumoniae AND beta-lactamase-producing H. influenzae and M. catarrhalis
  • Recommended dosage: 90 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate in 2 divided doses 1, 2

Clinical Decision Algorithm for AOM Treatment

First-Line Treatment (Standard Cases)

• High-dose amoxicillin (80-90 mg/kg/day in 2 divided doses) for:
  • Uncomplicated first episode of AOM
  • No recent antibiotic use
  • No concurrent conjunctivitis
  • No risk factors for resistant organisms 1

When to Use Augmentin Instead

Use high-dose amoxicillin-clavulanate when:

1. Patient has taken amoxicillin in the previous 30 days
2. Concurrent purulent conjunctivitis is present (strongly suggests H. influenzae)
3. Treatment failure with amoxicillin after 48-72 hours
4. Recurrent or persistent AOM
5. Coverage for M. catarrhalis is specifically desired 1

Efficacy Considerations

Hoberman et al. demonstrated superior efficacy of high-dose amoxicillin-clavulanate in eradicating S. pneumoniae (96%) from the middle ear compared to azithromycin 1. Another study showed that amoxicillin-clavulanate eradicated 96% of S. pneumoniae (including 92% of fully penicillin-resistant strains) and 89.7% of H. influenzae 3.

Side Effect Profile

• Amoxicillin: Generally well-tolerated with fewer gastrointestinal side effects
• Augmentin: Higher incidence of diarrhea due to clavulanate component 1, 4
  • A study showed 26% of children on standard Augmentin developed protocol-defined diarrhea 4
  • Newer formulations with reduced clavulanate concentrations may cause less diarrhea while maintaining efficacy 4

Common Pitfalls to Avoid

1. Overuse of Augmentin: Using Augmentin as first-line therapy for all AOM cases increases side effects without providing additional benefit in uncomplicated cases

2. Underdosing amoxicillin: Using standard-dose rather than high-dose amoxicillin may lead to treatment failure with intermediately resistant S. pneumoniae

3. Failing to switch to Augmentin when indicated: Not changing to amoxicillin-clavulanate after amoxicillin failure within 48-72 hours 1

4. Ignoring risk factors for resistant organisms: Recent antibiotic use, daycare attendance, and winter season increase risk of resistant pathogens

Treatment Duration

• Children <2 years: 10 days
• Children ≥2 years with mild/moderate illness: 5-7 days 1

In conclusion, while both medications are effective for treating AOM, high-dose amoxicillin remains the first-line treatment for most cases due to its efficacy, safety, low cost, and narrower antimicrobial spectrum. Augmentin should be reserved for specific situations where beta-lactamase-producing organisms are suspected or when initial amoxicillin treatment fails.