Amoxicillin Dosing for 9.07 kg Pediatric Patient Using 200mg/5mL Suspension
For a 9.07 kg child, administer 4.5 mL of the 200mg/5mL amoxicillin suspension twice daily (every 12 hours), which delivers approximately 360 mg per day (40 mg/kg/day) for mild to moderate infections, or 9 mL twice daily (approximately 720 mg per day, or 80 mg/kg/day) for severe infections or high-resistance areas. 1
Weight-Based Dosing Algorithm
The appropriate dose depends on the indication and severity:
For Mild to Moderate Respiratory Infections
- Standard dose: 45 mg/kg/day divided into 2 doses 1, 2
- For this 9.07 kg child: 45 mg/kg × 9.07 kg = 408 mg per day
- Divided into 2 doses = 204 mg per dose
- Using 200mg/5mL suspension: 5 mL twice daily (delivers 200 mg per dose, 400 mg/day total) 1
For Severe Infections or High Pneumococcal Resistance Areas
- High dose: 90 mg/kg/day divided into 2 doses 1, 2
- For this 9.07 kg child: 90 mg/kg × 9.07 kg = 816 mg per day
- Divided into 2 doses = 408 mg per dose
- Using 200mg/5mL suspension: 10 mL twice daily (delivers 400 mg per dose, 800 mg/day total) 1
Indication-Specific Guidance
Community-Acquired Pneumonia
- Children under 5 years with presumed bacterial pneumonia should receive 90 mg/kg/day in 2 divided doses (maximum 4 g/day) 1
- For this patient: 10 mL of 200mg/5mL suspension twice daily 1
- The high-dose regimen is endorsed by the Infectious Diseases Society of America (IDSA) and Pediatric Infectious Diseases Society (PIDS) to ensure coverage of penicillin-resistant Streptococcus pneumoniae 1
Group A Streptococcal Infections
- Dose: 50-75 mg/kg/day divided into 2 doses for 10 days 1
- For this 9.07 kg child: 50-75 mg/kg = 453-680 mg per day
- Using 200mg/5mL suspension: 6-8.5 mL twice daily 1
- Maximum single dose should not exceed 1,000 mg 1
Acute Otitis Media or Sinusitis (Uncomplicated)
- For children ≥2 years without risk factors: 45 mg/kg/day in 2 doses 1
- For this patient: 5 mL twice daily 1
High-Risk Situations Requiring Higher Dosing
Use 90 mg/kg/day (10 mL twice daily) if any of these apply: 1
- Age < 2 years
- Daycare attendance
- Recent antibiotic use (within past 30 days)
- Region with >10% penicillin-resistant S. pneumoniae
- Moderate-to-severe illness presentation
Critical Administration Details
Timing and Duration
- Administer at the start of meals to minimize gastrointestinal intolerance 2
- Treatment duration: 10 days for most respiratory infections 3
- For Group A Streptococcal infections: complete full 10-day course to prevent acute rheumatic fever 1, 2
- Minimum treatment: 48-72 hours beyond symptom resolution 3
Monitoring Response
- Children on adequate therapy should demonstrate clinical improvement within 48-72 hours 3
- If no improvement by 48-72 hours, reevaluation and further investigation are necessary 1
- Fever typically resolves within 24-48 hours for pneumococcal pneumonia, though cough may persist longer 1
Suspension Preparation and Storage
- Shake oral suspension well before each use 2
- After reconstitution, discard any unused portion after 14 days 2
- Refrigeration is preferable but not required 2
Common Pitfalls to Avoid
- Do not use the 875 mg tablet formulation in children under 40 kg 2
- For children under 3 months (12 weeks), maximum dose is 30 mg/kg/day divided every 12 hours due to immature renal function 2
- Avoid underdosing in high-risk situations—the difference between 45 and 90 mg/kg/day is clinically significant for resistant organisms 1, 4
- Do not prescribe based solely on clinical presentation for pharyngitis—rapid antigen detection test or throat culture is required because approximately 70% of sore throats are not streptococcal 1
When to Consider Amoxicillin-Clavulanate Instead
Switch to amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) if: 1
- Suspected β-lactamase-producing organisms (H. influenzae, M. catarrhalis)
- Incomplete H. influenzae type b vaccination
- Concurrent purulent acute otitis media
- Treatment failure after initial amoxicillin course