What is the recommended dose of amoxicillin (amoxicillin) for a child with streptococcal pharyngitis (strep throat) who weighs 28 pounds (#)?

Amoxicillin Dosing for a 28-Pound Child with Strep Throat

For a 28-pound (approximately 12.7 kg) child with streptococcal pharyngitis, the recommended dose of amoxicillin is 50 mg/kg/day once daily (635 mg) or 25 mg/kg/day twice daily (318 mg per dose) for 10 days. 1

Dosing Calculation and Options

• For a 28-pound (12.7 kg) child, the specific dosing options are:

  • Once-daily dosing: 50 mg/kg × 12.7 kg = 635 mg once daily 1, 2
  • Twice-daily dosing: 25 mg/kg × 12.7 kg = 318 mg twice daily 1

• The FDA label for amoxicillin confirms that a full 10-day course is required for streptococcal infections to prevent complications like acute rheumatic fever 3

Evidence-Based Rationale

• The American Academy of Family Physicians strongly recommends amoxicillin as first-line therapy for streptococcal pharyngitis in children 1

• Once-daily dosing has been shown to be as effective as multiple daily doses and may improve medication adherence 2, 4

• For Group A Streptococcus infections, amoxicillin has demonstrated superior clinical and bacteriological cure rates compared to penicillin in several studies 5, 6

Important Clinical Considerations

• Treatment must continue for a full 10 days, even if symptoms resolve earlier, to prevent acute rheumatic fever 1, 3

• Patients are generally considered non-contagious after 24 hours of antibiotic therapy 1

• The medication should be taken at the start of a meal to minimize gastrointestinal intolerance 3

Alternative Options for Special Circumstances

• For penicillin-allergic patients, alternatives include:

  • Cephalexin (if no anaphylactic reaction to penicillin): 20 mg/kg twice daily 1
  • Clindamycin: 7 mg/kg three times daily 1

• For treatment failures or recurrent infections, higher doses or alternative regimens may be considered:

  • Amoxicillin-clavulanate: 40 mg/kg/day of amoxicillin component in three divided doses 7, 1

Common Pitfalls to Avoid

• Underdosing is a common mistake that can lead to treatment failure and potential complications 5

• Stopping antibiotics early when symptoms improve can increase the risk of rheumatic fever 1, 3

• Using macrolides (like azithromycin) as first-line therapy should be avoided due to increasing resistance patterns unless there is a true penicillin allergy 1

• For young infants under 12 weeks (3 months), dosing should not exceed 30 mg/kg/day divided every 12 hours due to immature renal function 3