Dosing Assessment for Bacterial Tonsillitis in a 3-Year-Old, 22kg Child
The prescribed dose of 5ml twice daily is significantly underdosed and should be increased to achieve adequate bacterial eradication and prevent treatment failure. Without knowing the specific concentration of the Augmentin suspension, this dosing is likely insufficient for bacterial tonsillitis in this child.
Critical Dosing Calculation
For a 22kg child with bacterial tonsillitis (Group A Streptococcal pharyngitis), the recommended dosing is:
- Standard dose: 50-75 mg/kg/day of amoxicillin component divided into 2 doses for 10 days 1
- Calculated requirement: 22kg × 50-75 mg/kg = 1,100-1,650 mg total daily dose
- Per dose: 550-825 mg twice daily 1
Concentration-Specific Analysis
If using 400mg/5mL suspension (most common high-dose formulation):
- Current dose: 5mL × 2 = 400mg × 2 = 800mg/day total
- This provides only 36 mg/kg/day - well below the minimum 50 mg/kg/day recommended 1, 2
- Correct dose: 7-10mL twice daily (approximately 1,100-1,650mg daily) 1
If using 250mg/5mL suspension:
- Current dose: 5mL × 2 = 250mg × 2 = 500mg/day total
- This provides only 23 mg/kg/day - grossly inadequate 1
- Correct dose: 11-16.5mL twice daily 1
Treatment Duration Concern
The prescribed 7-day course is insufficient for Group A Streptococcal infections, which require:
- 10 days of treatment to prevent rheumatic fever and ensure bacterial eradication 1, 2
- Patients become non-contagious after only 24 hours of appropriate antibiotic therapy, but the full 10-day course must be completed 1
Clinical Implications of Underdosing
Using inadequate dosing risks:
- Treatment failure and persistent infection 3
- Development of antibiotic resistance through subtherapeutic drug concentrations 3
- Inadequate coverage against penicillin-intermediate Streptococcus pneumoniae if present 2, 4
- Potential complications including rheumatic fever if Group A Streptococcus is inadequately treated 1
Recommended Correction
Contact the prescribing physician immediately to clarify:
- The exact concentration of the Augmentin suspension prescribed 5
- Whether the intended dose was based on weight-appropriate calculations 1, 5
- Extension of treatment duration from 7 to 10 days 1, 2
Proper dosing should be:
- 50-75 mg/kg/day of amoxicillin component (1,100-1,650mg daily for this 22kg child) 1
- Divided into 2 doses given every 12 hours 1, 5
- Continued for 10 days total 1, 2
- Clinical improvement should be evident within 48-72 hours; if not, reevaluation is necessary 3, 1
Common Pitfall to Avoid
The most critical error here is assuming 5mL is an appropriate volume without confirming the suspension concentration - Augmentin comes in multiple concentrations (125mg/5mL, 250mg/5mL, 400mg/5mL), and the same volume delivers vastly different doses 5. Always verify the mg/mL concentration and calculate the exact mg/kg/day being delivered 1, 5.