Amoxicillin/Clavulanate for 6-Month-Old with Moraxella Infection
For a 6-month-old with Moraxella infection, treat with amoxicillin/clavulanate 45 mg/kg/day (amoxicillin component) divided into 2 doses for 10 days. 1, 2
Dosing Rationale
- Moraxella catarrhalis is universally a β-lactamase producer, requiring amoxicillin/clavulanate rather than amoxicillin alone 3, 4
- The standard dose of 45 mg/kg/day divided every 12 hours provides adequate coverage for β-lactamase-producing organisms in mild to moderate respiratory infections 5, 1
- For a 6-month-old infant (typical weight ~7-8 kg), this translates to approximately 315-360 mg per dose given twice daily 1
When to Use Higher Dosing
- Consider 90 mg/kg/day divided into 2 doses if the infant has any of the following risk factors: 1, 6
- Recent antibiotic exposure within past 30 days
- Daycare attendance
- Severe infection requiring hospitalization
- Geographic area with high pneumococcal resistance (>10%)
- Concurrent infection with penicillin-resistant S. pneumoniae
Treatment Duration
- Complete a full 10-day course for respiratory tract infections including pneumonia 1, 6
- Treatment should continue for a minimum of 48-72 hours beyond symptom resolution 7
- Never discontinue early even if clinical improvement occurs before completion 1
Monitoring and Expected Response
- Clinical improvement should be evident within 48-72 hours of initiating therapy 1, 6
- Fever typically resolves within 24-48 hours 6
- If no improvement by 48-72 hours, reevaluate immediately for resistant organisms, alternative diagnoses, or treatment failure 1, 2
Critical Considerations for Infants Under 12 Weeks
- For infants younger than 3 months, the FDA recommends a maximum dose of 30 mg/kg/day divided every 12 hours due to immature renal function 7
- However, at 6 months of age, standard pediatric dosing (45-90 mg/kg/day) is appropriate 1, 7
Administration Guidance
- Administer at the start of meals to minimize gastrointestinal intolerance 7
- Shake oral suspension well before each dose 7
- Refrigeration is preferable but not required; discard unused suspension after 14 days 7