What is the recommended dose of amoxicillin (amoxicillin) for a child weighing 52 pounds (approximately 23.6 kilograms)?

Amoxicillin Dosing for a 52-Pound Child

The standard amoxicillin dose for a 52-pound (23.6 kg) child depends on the indication, but for most common infections ranges from 20-50 mg/kg/day divided into 2-3 doses, with higher doses (80-90 mg/kg/day) reserved for resistant organisms or specific infections like acute otitis media.

Weight Conversion and Dosing Framework

A 52-pound child weighs approximately 23.6 kg, which is critical for accurate weight-based dosing calculations.

Standard Dosing by Indication

For Routine Infections (Pharyngitis, Skin Infections, UTI)

• Standard dose: 20-25 mg/kg/day divided every 8-12 hours 1
• For this 23.6 kg child: approximately 472-590 mg/day total
• Practical dosing: 250 mg three times daily OR 400 mg twice daily

For Acute Otitis Media (AOM) - Standard Dose

• Conventional dose: 40 mg/kg/day divided into three doses 2
• For this 23.6 kg child: approximately 944 mg/day total
• Practical dosing: 300-350 mg three times daily

For Acute Otitis Media - High-Dose Therapy

• High-dose regimen: 80-90 mg/kg/day for resistant organisms 2
• For this 23.6 kg child: approximately 1,888-2,124 mg/day total
• Practical dosing: 600-700 mg three times daily OR 900-1000 mg twice daily
• This higher dose is specifically indicated for recurrent or persistent AOM where penicillin-resistant Streptococcus pneumoniae is suspected 2

For Community-Acquired Pneumonia

• Lower dose: 35-50 mg/kg/day 3
• For this 23.6 kg child: approximately 826-1,180 mg/day total
• Practical dosing: 400 mg twice daily OR 275-400 mg three times daily
• Higher dose: 70-90 mg/kg/day for more severe cases 3
• For this 23.6 kg child: approximately 1,652-2,124 mg/day total
• Practical dosing: 700-800 mg twice daily OR 550-700 mg three times daily

Critical Dosing Considerations

Amoxicillin/Clavulanate Formulations

If using amoxicillin/clavulanate (Augmentin) instead of amoxicillin alone:

• Standard formulation: 40/10 mg/kg/day in three divided doses 2
• High-dose formulation (ES-600): 90/6.4 mg/kg/day in two divided doses for resistant pathogens 2
• The high-dose formulation provides better coverage for penicillin-intermediate and penicillin-resistant S. pneumoniae (MIC ≤2 mg/L) 2

Absorption and Bioavailability

• Amoxicillin is well-absorbed orally, achieving blood levels 2-2.5 times higher than ampicillin 1
• Administration with food may improve gastrointestinal tolerability, particularly with amoxicillin/clavulanate formulations 2
• Twice-daily dosing generally causes less diarrhea than three-times-daily dosing 2

Common Pitfalls to Avoid

• Do not underdose for resistant organisms: Standard 40 mg/kg/day dosing may be inadequate for penicillin-resistant S. pneumoniae; use 80-90 mg/kg/day when resistance is suspected 2
• Do not confuse amoxicillin with amoxicillin/clavulanate dosing: The clavulanate component has dose-dependent gastrointestinal side effects, so high-dose formulations use a different ratio (16:1 vs 7:1) 2
• Do not exceed maximum adult doses: Even with high-dose regimens, do not exceed 3000 mg/day total amoxicillin
• Verify renal function: Dose adjustment is required for significant renal impairment 4

Practical Prescribing Example

For a 52-pound child with uncomplicated acute otitis media:

• Start with standard dose: 40 mg/kg/day = 944 mg/day
• Practical prescription: Amoxicillin 300 mg PO three times daily for 10 days

For a 52-pound child with recurrent or persistent AOM (failed initial therapy):

• Use high-dose: 80-90 mg/kg/day = 1,888-2,124 mg/day
• Practical prescription: Amoxicillin 700 mg PO three times daily for 10 days
• OR Amoxicillin/clavulanate ES-600 (90/6.4 mg/kg/day) twice daily 2

For a 52-pound child with community-acquired pneumonia:

• Evidence supports both lower (35-50 mg/kg/day) and higher (70-90 mg/kg/day) doses as equally effective 3
• Practical prescription: Amoxicillin 400 mg PO twice daily for 5-7 days
• Higher doses may be used for more severe presentations but do not reduce retreatment rates 3