What is the appropriate dosage of Amoxicillin for a 60-pound pediatric patient using the 400mg/5ml formulation?

Amoxicillin Dosing for a 60-Pound Pediatric Patient Using 400mg/5mL Formulation

For a 60-pound (27.2 kg) child, administer 6.8 mL of amoxicillin 400mg/5mL suspension twice daily for most common infections, or 13.6 mL twice daily for severe infections or high-resistance areas. 1

Weight-Based Calculation

• A 60-pound child weighs approximately 27.2 kg (60 ÷ 2.2 = 27.2 kg) 1
• Using the 400mg/5mL formulation, each mL contains 80 mg of amoxicillin 1

Standard Dosing Algorithm

For mild to moderate infections (respiratory tract, skin, uncomplicated):

• The recommended dose is 45 mg/kg/day divided into 2 doses 2, 1, 3
• Calculation: 27.2 kg × 45 mg/kg/day = 1,224 mg/day 1
• Per dose: 1,224 mg ÷ 2 = 612 mg per dose 1
• Volume: 612 mg ÷ 80 mg/mL = 7.65 mL per dose (can round to 7.5 mL or 8 mL for practical administration) 1
• Alternatively, using 25 mg/kg per dose: 27.2 kg × 25 mg/kg = 680 mg = 8.5 mL per dose 3

For severe infections or high pneumococcal resistance areas:

• The recommended dose is 90 mg/kg/day divided into 2 doses 1, 3
• Calculation: 27.2 kg × 90 mg/kg/day = 2,448 mg/day 1
• Per dose: 2,448 mg ÷ 2 = 1,224 mg per dose 1
• Volume: 1,224 mg ÷ 80 mg/mL = 15.3 mL per dose (can round to 15 mL) 1

Indication-Specific Dosing

Community-acquired pneumonia (mild to moderate):

• Use 45 mg/kg/day in 2 doses = 7.5-8.5 mL twice daily 1

Community-acquired pneumonia (severe) or high-resistance areas:

• Use 90 mg/kg/day in 2 doses = 15 mL twice daily 1
• This higher dose is indicated for children <2 years, recent antibiotic exposure within 30 days, daycare attendance, or areas with >10% penicillin-resistant S. pneumoniae 1

Group A Streptococcal pharyngitis (strep throat):

• Use 50 mg/kg/day in 2 doses for 10 days 4
• Calculation: 27.2 kg × 50 mg/kg/day = 1,360 mg/day 4
• Per dose: 680 mg = 8.5 mL twice daily for 10 days 4

Acute otitis media (uncomplicated):

• Use 45 mg/kg/day in 2 doses = 7.5-8.5 mL twice daily 1
• If recent antibiotic use within 4-6 weeks or treatment failure, consider high-dose amoxicillin-clavulanate instead 1

Critical Treatment Considerations

Treatment duration:

• Most respiratory infections: 7-10 days 1
• Pneumonia specifically: 10 days 1
• Streptococcal pharyngitis: 10 days (mandatory to prevent acute rheumatic fever) 4, 3
• Continue for minimum 48-72 hours beyond symptom resolution 3

Clinical monitoring:

• Children should show clinical improvement within 48-72 hours 1
• If no improvement by 48-72 hours, reevaluation is necessary and consider atypical pathogens or treatment failure 1
• Fever typically resolves within 24-48 hours for pneumococcal infections 1

Common Pitfalls to Avoid

Avoid underdosing:

• The older 40 mg/kg/day dosing is inadequate for current resistance patterns 5, 6
• Current evidence supports 45-90 mg/kg/day depending on severity 1

Maximum daily dose:

• Do not exceed 4,000 mg/day regardless of weight 1
• For this 27.2 kg child, even the high-dose regimen (2,448 mg/day) is well below this maximum 1

When to use amoxicillin-clavulanate instead:

• Treatment failure after 48-72 hours of amoxicillin alone 1
• Recent antibiotic exposure within past 30 days 1
• Suspected β-lactamase-producing organisms (H. influenzae, M. catarrhalis) 1
• Incomplete H. influenzae type b vaccination with concurrent purulent otitis media 1

Administration Instructions

• Administer at the start of meals to minimize gastrointestinal intolerance 3
• Shake suspension well before each use 3
• Store reconstituted suspension in refrigerator (preferred but not required) 3
• Discard unused suspension after 14 days 3