What is the recommended dosage of amoxicillin (amoxicillin) for a patient weighing 54 pounds?

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Amoxicillin Dosage for a 54-Pound Patient

For a 54-pound (approximately 24.5 kg) child, the recommended amoxicillin dosage is 40-50 mg/kg/day divided into 2-3 doses, which equals approximately 980-1225 mg per day or 325-408 mg per dose given three times daily. 1

Dosage Calculation Based on Weight and Indication

  • The FDA-approved amoxicillin dosage for children weighing less than 40 kg is 20-40 mg/kg/day divided into doses every 8 hours for mild to moderate infections, and 40-45 mg/kg/day divided into doses every 8-12 hours for severe infections 1
  • For most common pediatric infections, including ear/nose/throat and skin/skin structure infections, the recommended dosage is 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours for mild/moderate infections 1
  • For severe infections or lower respiratory tract infections, the recommended dosage is 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours 1
  • For Group A Streptococcal infections, amoxicillin should be given at 50-75 mg/kg/day in 2 doses 2

Specific Dosing Recommendations by Infection Type

For Streptococcal Pharyngitis

  • Amoxicillin 50 mg/kg once daily (maximum = 1,000 mg) or 25 mg/kg twice daily (maximum = 500 mg) for 10 days 2
  • Treatment should continue for a minimum of 10 days for any infection caused by Streptococcus pyogenes to prevent acute rheumatic fever 1

For Skin and Soft Tissue Infections

  • For mild to moderate skin infections, 40 mg/kg/day divided into three doses is appropriate 3
  • For a 24.5 kg child, this equals approximately 980 mg/day or about 325 mg per dose given three times daily 3

For Otitis Media and Respiratory Infections

  • Higher doses (75-90 mg/kg/day) may be needed for acute otitis media, particularly when dealing with resistant organisms 4
  • For community-acquired pneumonia, 35-50 mg/kg/day has been shown to be non-inferior to higher doses (70-90 mg/kg/day) 5

Administration Considerations

  • Amoxicillin should be taken at the start of a meal to minimize gastrointestinal intolerance 1
  • For oral suspension, the medication should be shaken well before using 1
  • Treatment should be continued for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic 1

Dosing Frequency Options

  • Twice-daily dosing (every 12 hours) has been shown to be a feasible alternative to three-times-daily dosing in many cases 6, 7
  • For twice-daily dosing, consider using 45 mg/kg/day divided into two doses 1
  • For three-times-daily dosing, use 40 mg/kg/day divided into three doses 1

Common Pitfalls and Caveats

  • Underdosing amoxicillin may lead to treatment failure, particularly with resistant Streptococcus pneumoniae 4
  • The current standard amoxicillin dosing of 40 mg/kg/day may be inadequate for resistant organisms, particularly during viral coinfection 4
  • Any unused portion of reconstituted suspension must be discarded after 14 days 1
  • Refrigeration of the reconstituted suspension is preferable but not required 1

For this 54-pound (24.5 kg) patient, the appropriate dosage would depend on the specific infection being treated, but for most common pediatric infections, 325-408 mg per dose given three times daily would be appropriate.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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