How should I treat a 3-year-old with acute otitis media and group A streptococcal pharyngitis who is allergic to amoxicillin?

Treatment for Pediatric Acute Otitis Media and Strep Throat with Amoxicillin Allergy

For a 3-year-old with both acute otitis media and streptococcal pharyngitis who is allergic to amoxicillin, prescribe cefdinir 14 mg/kg/day once daily for 10 days if the allergy is non-immediate (e.g., mild rash), or azithromycin 12 mg/kg once daily (maximum 500 mg) for 5 days if the allergy is immediate/anaphylactic (e.g., hives, angioedema, bronchospasm). 1, 2

Critical First Step: Determine the Type of Amoxicillin Allergy

• Non-immediate (delayed) reactions such as mild rash occurring >1 hour after exposure carry only 0.1% cross-reactivity with second- and third-generation cephalosporins, making cefdinir safe and preferred 1, 3
• Immediate/anaphylactic reactions (anaphylaxis, angioedema, urticaria within 1 hour) carry up to 10% cross-reactivity with all beta-lactams including cephalosporins, requiring complete avoidance of this drug class 2, 3

Treatment Algorithm Based on Allergy Type

For Non-Immediate Amoxicillin Allergy (Preferred Approach)

Prescribe cefdinir 14 mg/kg/day once daily for 10 days 1, 4

• Cefdinir provides excellent coverage for both Group A Streptococcus (strep throat) and the typical acute otitis media pathogens: Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 1, 3
• The once-daily dosing significantly improves adherence in young children compared to twice- or thrice-daily regimens 1
• Cross-reactivity risk with second/third-generation cephalosporins is negligible (0.1%) in patients with non-severe penicillin allergy 1
• A full 10-day course is mandatory to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever 2, 1

Alternative cephalosporin options for non-immediate allergy:

• Cefuroxime 30 mg/kg/day divided twice daily for 10 days 1
• Cefpodoxime 10 mg/kg/day divided twice daily for 10 days 1

For Immediate/Anaphylactic Amoxicillin Allergy

Prescribe azithromycin 12 mg/kg once daily (maximum 500 mg) for 5 days 2, 5

• Azithromycin is the only antibiotic that requires just 5 days due to its prolonged tissue half-life, making it more convenient for families 2, 3
• It provides adequate coverage for both strep throat and acute otitis media pathogens 5, 4
• Important caveat: Macrolide resistance among Group A Streptococcus ranges from 5-8% in the United States and varies geographically 2, 3
• Clinical success rates for acute otitis media with azithromycin are 83-89% at end of treatment 5

Alternative for immediate allergy:

• Clindamycin 7 mg/kg three times daily (maximum 300 mg/dose) for 10 days plus a second agent for H. influenzae and M. catarrhalis coverage (e.g., cefixime or trimethoprim-sulfamethoxazole) 2, 3
• Clindamycin alone has only ~1% resistance among Group A Streptococcus but does not adequately cover the beta-lactamase-producing organisms common in acute otitis media 2, 3

Essential Pain Management (Regardless of Antibiotic Choice)

• Immediately administer weight-based acetaminophen or ibuprofen for ear pain, sore throat, and fever 1
• Analgesics provide relief within the first 24 hours, whereas antibiotics provide no symptomatic benefit in the first 24 hours 1
• Continue pain medication throughout the acute phase as needed 1
• Avoid aspirin in children due to Reye syndrome risk 2

Critical Pitfalls to Avoid

• Do not use cephalosporins if the patient had anaphylaxis, angioedema, or immediate urticaria to amoxicillin due to the 10% cross-reactivity risk 2, 1, 3
• Do not shorten the antibiotic course below 10 days (except azithromycin's 5-day regimen), as this dramatically increases treatment failure and rheumatic fever risk 2, 1
• Do not prescribe trimethoprim-sulfamethoxazole (Bactrim) for strep throat, as it fails to eradicate Group A Streptococcus in 20-25% of cases 2, 3
• Do not use macrolides (azithromycin, clarithromycin) as first-line when cephalosporins can be safely used, as macrolides have higher resistance rates and lower efficacy 6

Reassessment Protocol

• Re-evaluate at 48-72 hours if symptoms worsen or fail to improve 1
• If cefdinir fails, switch to intramuscular ceftriaxone 50 mg/kg once daily for 3 days (superior to single-dose regimen) 1
• If azithromycin fails, consider clindamycin with adjunctive coverage for otitis media pathogens 2, 3

Why This Dual-Infection Requires Special Consideration

• Standard strep throat treatment (e.g., clindamycin alone) does not adequately cover beta-lactamase-producing H. influenzae and M. catarrhalis, which cause 35-50% of acute otitis media cases 1, 5, 7
• Cefdinir and azithromycin are among the few non-amoxicillin options that effectively cover both Group A Streptococcus and the typical acute otitis media pathogens 1, 4
• First-generation cephalosporins (cephalexin, cefadroxil) are excellent for strep throat but have inadequate coverage for beta-lactamase-producing organisms in acute otitis media 1, 7

Expected Post-Treatment Course

• After successful antibiotic treatment of acute otitis media, 60-70% of children have middle ear effusion at 2 weeks, declining to 40% at 1 month and 10-25% at 3 months 1
• This post-treatment effusion (otitis media with effusion) requires monitoring but not additional antibiotics unless it persists >3 months with hearing loss 1