What is the recommended first‑line therapy for acute otitis media, including drug choice, dosage, and duration for children and adults, alternative regimens for penicillin‑allergic patients, criteria for observation without antibiotics, and management of chronic otitis media with effusion and indications for referral?

Treatment of Acute Otitis Media

High-dose amoxicillin (80–90 mg/kg/day divided twice daily for children; 1.5–4 g/day for adults) is the first-line antibiotic for acute otitis media, with immediate pain control using acetaminophen or ibuprofen required for every patient regardless of antibiotic decision. 1, 2

Diagnostic Confirmation

• Acute otitis media requires all three elements: acute onset of symptoms, presence of middle ear effusion (documented by impaired tympanic membrane mobility, bulging, or air-fluid level on pneumatic otoscopy), and signs of middle ear inflammation (moderate-to-severe bulging or new otorrhea not due to otitis externa). 1, 2
• Pneumatic otoscopy is essential—isolated tympanic membrane redness without effusion does not constitute acute otitis media and should not be treated with antibiotics. 1, 2
• The three most common bacterial pathogens are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. 1, 2, 3

Immediate Pain Management (All Patients)

• Initiate weight-based acetaminophen or ibuprofen immediately for all patients with otalgia, as analgesics provide relief within 24 hours whereas antibiotics provide no symptomatic benefit in the first 24 hours. 1, 2
• Continue analgesics throughout the acute phase, as 30% of children younger than 2 years still have pain or fever after 3–7 days of antibiotic therapy. 2

Decision Algorithm: Observation vs. Immediate Antibiotics

Immediate Antibiotics Required:

• All children < 6 months of age 2
• Children 6–23 months with bilateral acute otitis media (regardless of severity) 2
• Children 6–23 months with severe acute otitis media (moderate-to-severe otalgia, otalgia ≥ 48 hours, or fever ≥ 39°C/102.2°F) 2
• Children ≥ 24 months with severe acute otitis media 2
• All adults with acute otitis media (observation not established for adults) 1
• Any patient when reliable follow-up cannot be ensured 2

Observation Without Immediate Antibiotics Appropriate:

• Children 6–23 months with non-severe unilateral acute otitis media 2
• Children ≥ 24 months with non-severe acute otitis media (unilateral or bilateral) 2

Observation requires: a safety-net prescription to be filled only if symptoms worsen or fail to improve within 48–72 hours, plus a reliable follow-up mechanism (scheduled return visit or telephone contact). 2

First-Line Antibiotic Selection

Standard First-Line: High-Dose Amoxicillin

• Pediatric dosing: 80–90 mg/kg/day divided twice daily (maximum 2 g per dose) 1, 2, 3
• Adult dosing: 1.5–4 g/day 2
• High-dose amoxicillin achieves 92% eradication of S. pneumoniae (including penicillin-nonsusceptible strains with MIC ≤ 2.0 μg/mL), 84% eradication of beta-lactamase-negative H. influenzae, and 62% eradication of beta-lactamase-positive H. influenzae. 1

When to Use Amoxicillin-Clavulanate Instead:

• Patient received amoxicillin in the previous 30 days 1, 2
• Concurrent purulent conjunctivitis (suggests H. influenzae infection) 1, 2
• Recurrent acute otitis media unresponsive to amoxicillin 1, 2
• Dosing: 90 mg/kg/day (amoxicillin component) + 6.4 mg/kg/day (clavulanate) divided twice daily for children; 2000 mg/125 mg twice daily for adults 1, 2
• Twice-daily dosing causes significantly less diarrhea (10–13%) than three-times-daily dosing (≈35%) with equivalent efficacy. 1

Treatment Duration

Children:

• < 2 years: 10 days (regardless of severity) 2, 3
• 2–5 years: 7 days for mild-to-moderate disease; 10 days for severe disease 2, 3
• ≥ 6 years: 5–7 days for mild-to-moderate disease; 10 days for severe disease 2, 3

Adults:

• 5–7 days for uncomplicated cases (extrapolated from sinusitis evidence, as adults have different immune responses and lower risk of treatment failure) 1

Penicillin-Allergic Patients

Non-Type I (Non-Anaphylactic) Penicillin Allergy:

• Preferred: Cefdinir 14 mg/kg/day once daily (or divided twice daily) for children; 600 mg once daily for adults 1, 2
• Alternatives: Cefuroxime 30 mg/kg/day divided twice daily (500 mg twice daily for adults) or cefpodoxime 10 mg/kg/day divided twice daily 1, 2
• Cross-reactivity between penicillins and second/third-generation cephalosporins is negligible (≈0.1%), far lower than the historically cited 10%. 1, 2

Type I (Anaphylactic) Penicillin Allergy:

• All cephalosporins are contraindicated in documented Type I hypersensitivity. 1
• Use macrolides: Azithromycin or clarithromycin, though bacterial failure rates are 20–25% due to pneumococcal resistance exceeding 40%. 1, 2, 3
• Do not use trimethoprim-sulfamethoxazole (TMP-SMX) as first-line due to high resistance rates (≈50% against S. pneumoniae). 1

Management of Treatment Failure

• Reassess at 48–72 hours if symptoms worsen or fail to improve to confirm diagnosis and exclude other causes. 1, 2, 3

Treatment Failure Algorithm:

1. If initially observed: Start high-dose amoxicillin 2
2. If amoxicillin fails: Switch to amoxicillin-clavulanate (90 mg/kg/day) 1, 2
3. If amoxicillin-clavulanate fails: Intramuscular ceftriaxone 50 mg/kg once daily for 3 consecutive days (superior to single-dose regimen) 1, 2
4. After multiple failures: Consider tympanocentesis with culture and susceptibility testing 2, 3

Do not use trimethoprim-sulfamethoxazole or erythromycin-sulfisoxazole for treatment failures due to substantial resistance. 2

Otitis Media with Effusion (Post-Treatment Effusion)

• 60–70% of children have middle ear effusion at 2 weeks after successful treatment, declining to 40% at 1 month and 10–25% at 3 months. 2, 3
• Do not prescribe antibiotics for persistent effusion without acute symptoms—this is otitis media with effusion, not acute otitis media. 2, 4
• Watchful waiting for 3 months with age-appropriate hearing testing is recommended. 2
• Refer to otolaryngology if bilateral effusion persists > 3 months with hearing loss, language delay, or significant effect on child's well-being. 2, 4

Recurrent Acute Otitis Media

• Definition: ≥ 3 episodes in 6 months or ≥ 4 episodes in 12 months (with ≥ 1 episode in the preceding 6 months) 2
• Consider tympanostomy tube placement for recurrent acute otitis media (failure rates: 21% for tubes alone, 16% for tubes with adenoidectomy). 2
• Long-term prophylactic antibiotics are not recommended due to modest benefit that does not justify antibiotic resistance risks. 2

Prevention Strategies

• Pneumococcal conjugate vaccine (PCV-13) and annual influenza vaccination 2, 3
• Encourage breastfeeding for at least 6 months 2, 5
• Reduce or eliminate pacifier use after 6 months of age 2
• Eliminate tobacco smoke exposure 2, 3
• Minimize daycare attendance when possible 2

Critical Pitfalls to Avoid

• Do not confuse otitis media with effusion for acute otitis media—isolated middle ear fluid without acute inflammation does not require antibiotics. 1, 2
• Antibiotics do not prevent complications: 33–81% of children who develop acute mastoiditis had received prior antibiotics. 2
• NSAIDs at anti-inflammatory doses and corticosteroids have not demonstrated efficacy for acute otitis media treatment. 1, 2
• Do not use fluoroquinolones as first-line therapy due to antimicrobial resistance concerns and side effects. 1, 3
• Do not extend the duration of a failing antibiotic—switch to a different agent with broader coverage instead. 1, 2