Amoxicillin Dosing for Acute Otitis Media
For acute otitis media, prescribe high-dose amoxicillin at 80-90 mg/kg/day divided into 2 doses daily, which provides optimal coverage against drug-resistant Streptococcus pneumoniae while maintaining safety and efficacy. 1, 2
Standard Dosing Recommendations
High-dose amoxicillin (80-90 mg/kg/day in 2 divided doses) is the first-line treatment for most children with acute otitis media, justified by its effectiveness against common bacterial pathogens, safety profile, low cost, acceptable taste, and narrow microbiologic spectrum. 1, 2
The twice-daily dosing regimen is specifically recommended because it is associated with significantly less diarrhea compared to three-times-daily dosing (14% vs 34% incidence). 1, 3, 4
For practical prescribing, a child weighing 19.5 kg should receive approximately 780-880 mg twice daily (total daily dose 1560-1755 mg/day). 2
Treatment Duration
Children over 2 years with uncomplicated acute otitis media can be treated for 5-7 days. 2
When to Use Amoxicillin-Clavulanate Instead
Switch to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses) as first-line therapy in these specific situations: 1, 2
- Child received amoxicillin within the previous 30 days
- Concurrent purulent conjunctivitis is present
- Coverage for beta-lactamase-producing Haemophilus influenzae or Moraxella catarrhalis is desired
Penicillin Allergy Alternatives
For non-type I hypersensitivity reactions to penicillin, prescribe cefdinir (14 mg/kg/day in 1-2 doses), cefpodoxime, or cefuroxime (30 mg/kg/day). 1
The WHO guidelines recommend amoxicillin as first choice and amoxicillin-clavulanate as second choice, deliberately excluding ceftriaxone and cefuroxime from routine recommendations to reduce emphasis on empiric coverage of penicillin-resistant Streptococcus pneumoniae. 1
Reassessment and Treatment Failure
Reassess the patient at 48-72 hours if symptoms fail to improve or worsen. 1, 2
If treatment failure occurs (defined as worsening condition, persistence of symptoms beyond 48 hours, or no improvement by 48-72 hours), switch to amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) or consider ceftriaxone (50 mg/kg IM/IV for 3 days). 1, 2
Beta-lactamase-producing Haemophilus influenzae is the most common cause of amoxicillin treatment failure, accounting for 64% of bacteriologic failures in one study. 5
Observation Option (Watchful Waiting)
For children 6 months to 2 years with non-severe illness and uncertain diagnosis, or children ≥2 years without severe symptoms, observation without antibiotics for 48-72 hours is an acceptable option with assurance of follow-up and symptomatic relief. 1
This approach should not be used for children <6 months or those with severe symptoms (moderate-to-severe otalgia, otalgia >48 hours, or temperature ≥39°C). 1
Important Clinical Considerations
High-dose amoxicillin achieves middle ear fluid levels exceeding the minimum inhibitory concentration for approximately 87% of Streptococcus pneumoniae isolates, including intermediately resistant strains. 1
The bacteriologic efficacy of high-dose amoxicillin is 92% for Streptococcus pneumoniae, 84% for beta-lactamase-negative Haemophilus influenzae, but only 62% for beta-lactamase-positive Haemophilus influenzae. 5
Pain management should be addressed concurrently during the first 24 hours of illness, regardless of antibiotic use. 2
For obese children, prescribing patterns often deviate from guidelines, with physicians frequently capping doses at the standard adult maximum (1500 mg/day) rather than following weight-based dosing. 6 However, weight-based dosing (80-90 mg/kg/day) should be maintained even when it exceeds standard adult doses to ensure adequate coverage against resistant pathogens. 1, 2