Amoxicillin Ear Drops Are Not Used for Ear Infections
Amoxicillin is not available as ear drops and should never be administered topically into the ear canal for middle ear infections (acute otitis media). For an 18-month-old with acute otitis media, amoxicillin must be given orally at a dose of 80-90 mg/kg/day divided into two doses daily 1, 2.
Critical Distinction: Topical vs. Oral Therapy
Middle Ear Infections (Acute Otitis Media)
- Oral amoxicillin is the first-line treatment for acute otitis media in children, including 18-month-olds 1, 2, 3, 4
- The recommended dose is 80-90 mg/kg/day divided into two doses (high-dose amoxicillin) 1, 2, 4
- For an average 18-month-old weighing approximately 11 kg, this equals roughly 440-495 mg per dose, given twice daily 2
- Treatment duration is typically 5-10 days 2, 4
When Topical Ear Drops ARE Used
Topical antibiotic ear drops are only appropriate for:
- Acute otitis externa (outer ear canal infection, "swimmer's ear") - where quinolone drops like ofloxacin or ciprofloxacin-dexamethasone are used 1
- Tympanostomy tube otorrhea (drainage through ear tubes) - where topical quinolone drops are first-line therapy 1
Why This Matters
The tympanic membrane (eardrum) is intact in acute otitis media, preventing topical medications from reaching the infected middle ear space 1. Attempting to treat middle ear infections with ear drops would be completely ineffective and delay appropriate treatment 1.
Common Pitfall to Avoid
- Never prescribe topical ear drops for acute otitis media - this is a fundamental error that occurs when providers confuse otitis media (middle ear) with otitis externa (outer ear canal) 1
- Systemic antibiotics like oral amoxicillin are required because the infection is behind the eardrum, not in the ear canal 3, 4
Specific Dosing for an 18-Month-Old
For a typical 18-month-old (approximately 11 kg):
- Total daily dose: 880-990 mg per day (80-90 mg/kg/day) 1, 2
- Divided into: 440-495 mg twice daily 2, 4
- Duration: 10 days for children under 2 years 2, 4
When to Consider Amoxicillin-Clavulanate Instead
Switch to amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) if 1, 2, 4:
- The child received amoxicillin in the previous 30 days
- Concurrent purulent conjunctivitis is present
- No improvement after 48-72 hours of amoxicillin therapy
- History of recurrent AOM unresponsive to amoxicillin
Rationale for High-Dose Oral Therapy
High-dose amoxicillin (80-90 mg/kg/day) is necessary due to increasing penicillin-resistant Streptococcus pneumoniae 2, 3, 5, 6. Standard-dose amoxicillin (40-45 mg/kg/day) is inadequate for resistant organisms, particularly when viral coinfection is present 5, 7, 6.