Co-amoxiclav Dosing for Pediatric UTI in a 2-Year-Old
For a 2-year-old child with a UTI, administer co-amoxiclav (amoxicillin-clavulanate) suspension at 40-90 mg/kg/day of the amoxicillin component, divided into 2-3 doses daily, for 7-14 days. 1
Specific Dosing Recommendations
The most practical dosing regimen is 45 mg/kg/day divided into 3 doses OR 90 mg/kg/day divided into 2 doses of the amoxicillin component. 2 This translates to using the 457 mg/5mL suspension (which contains 400 mg amoxicillin and 57 mg clavulanate per 5mL):
- For twice-daily dosing: Calculate 90 mg/kg/day of amoxicillin divided into 2 doses
- For three-times-daily dosing: Calculate 45 mg/kg/day of amoxicillin divided into 3 doses
The maximum daily dose should not exceed 4000 mg of amoxicillin. 2
Treatment Duration
Treat for 7-14 days total. 1 The American Academy of Pediatrics specifically recommends this duration for pediatric UTIs, as shorter courses (1-3 days) have proven inferior for febrile UTIs. 1
For uncomplicated cystitis with good clinical response, 5-7 days may be sufficient. 3
For pyelonephritis or febrile UTI, complete the full 10-14 days of therapy. 3
Clinical Efficacy Evidence
Co-amoxiclav demonstrates excellent efficacy in pediatric UTIs:
Achieves 96% cure rate in first-time UTIs and 89% in recurrent UTIs when dosed at 40 mg/kg/day for 5 days. 4
Studies show comparable efficacy to cefixime, with good safety profiles in children. 5
The combination is particularly valuable when organisms are resistant to amoxicillin alone, as clavulanate extends coverage against β-lactamase-producing bacteria. 4, 6
Important Clinical Considerations
If the child appears toxic, is unable to tolerate oral medications, or has complicated pyelonephritis, initiate parenteral therapy first (ceftriaxone or gentamicin) until clinical improvement occurs (typically 24-48 hours), then switch to oral co-amoxiclav to complete therapy. 1, 3
Monitoring Response:
- Expect clinical improvement within 2-3 days if therapy is effective. 3
- If no improvement by 48-72 hours, reassess and adjust based on culture sensitivities. 1
Tolerance Optimization:
- If gastrointestinal side effects occur (reported in 12% of cases), switch from 12-hour to 8-hour dosing intervals to improve tolerance. 4
- The suspension formulation is generally well-tolerated with no serious adverse effects reported in pediatric studies. 7
Antimicrobial Susceptibility Context
While co-amoxiclav is an appropriate choice, be aware of local resistance patterns:
- Amoxicillin-clavulanate susceptibility rates vary (69-100% in comparative studies). 5
- Alternative agents with higher susceptibility rates include gentamicin (97.5%), ticarcillin-clavulanate (94.2%), and nitrofurantoin (93.3%). 1
- Always adjust therapy based on culture and sensitivity results when available. 1, 3