What antibiotics are used to treat acute otitis media (ear infection)?

Antibiotics for Acute Otitis Media

First-Line Treatment

High-dose amoxicillin (80-90 mg/kg/day divided twice daily) is the first-line antibiotic for acute otitis media in patients without penicillin allergy. 1

• This recommendation is based on amoxicillin's efficacy against the most common bacterial pathogens (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis), favorable safety profile, and low cost. 1
• The high-dose regimen (80-90 mg/kg/day) is critical because standard dosing (40 mg/kg/day) is inadequate to eradicate resistant S. pneumoniae, particularly when viral coinfection is present. 2
• Treatment duration should be 10 days for most cases, though this was derived from historical practice rather than definitive evidence. 3

When to Initiate Antibiotics Immediately

Immediate antibiotic therapy is mandatory for:

• All children under 6 months with AOM 1
• Children 6-23 months with bilateral AOM or severe symptoms 1
• Any child with severe AOM (moderate-to-severe otalgia, otalgia lasting ≥48 hours, or temperature ≥39°C) 1

Watchful waiting (observation without immediate antibiotics) may be appropriate for:

• Children over 2 years with nonsevere unilateral AOM 1
• This approach requires reliable follow-up and ability to initiate antibiotics if symptoms worsen or fail to improve within 48-72 hours 3

Alternative First-Line Options for Penicillin Allergy

For non-type I penicillin allergy:

• Cefdinir, cefpodoxime, or cefuroxime are recommended alternatives 4

For true type I penicillin allergy (anaphylaxis):

• Azithromycin may be used, though it should NOT be used as a substitute for treatment failure with amoxicillin due to increasing resistance 1
• Erythromycin-sulfisoxazole is another option specifically for beta-lactam allergies 4

Management of Treatment Failure

Treatment failure is defined as worsening symptoms, persistence beyond 48-72 hours, or recurrence within 4 days of completing therapy. 4

Step-wise approach for treatment failure:

1. If initially treated with amoxicillin: Switch to amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) 3

2. If amoxicillin-clavulanate or oral third-generation cephalosporins fail: Use intramuscular ceftriaxone 50 mg/kg for 3 days (superior to single-dose regimen) 3, 4

3. For multiple treatment failures: Consider tympanocentesis for culture and susceptibility testing before proceeding to unconventional agents 3

4. Salvage therapy options (when tympanocentesis unavailable):

   • Clindamycin with or without coverage for H. influenzae and M. catarrhalis (cefdinir, cefixime, or cefuroxime) 3
   • For multidrug-resistant S. pneumoniae serotype 19A: Consider levofloxacin or linezolid after infectious disease consultation 3

Important Caveats and Pitfalls

Avoid these common errors:

• Do not use trimethoprim-sulfamethoxazole or erythromycin-sulfisoxazole for treatment failure due to substantial pneumococcal resistance 3
• Do not switch to azithromycin for treatment failure unless the patient has a true penicillin allergy and cannot tolerate cephalosporins 1
• Do not confuse otitis media with effusion (OME) with AOM - OME does not warrant antibiotic therapy and represents fluid without acute infection 3, 1
• Do not prescribe antibiotics based solely on tympanic membrane redness without evidence of middle ear effusion and acute symptoms 4

Pain Management

Address pain immediately with oral analgesics (acetaminophen or ibuprofen) regardless of antibiotic decision. 4

• Pain relief is a primary treatment goal and should not be considered peripheral to antibiotic therapy 4

Adult-Specific Considerations

For adults with AOM:

• Amoxicillin-clavulanate is preferred as first-line therapy (rather than amoxicillin alone) because adults have higher likelihood of beta-lactamase-producing organisms 4
• Adults typically require antibiotic therapy rather than observation, unlike children where watchful waiting may be appropriate 4
• Treatment duration should be 8-10 days for most cases, with 5 days acceptable for uncomplicated cases 4