Amoxicillin Dosing for Strep Throat in a 25 kg Child
For a 25 kg child with strep throat, give amoxicillin 1,250 mg once daily (50 mg/kg × 25 kg) OR 625 mg twice daily (25 mg/kg × 25 kg per dose) for 10 days. 1
Recommended Dosing Regimen
The American Academy of Family Physicians recommends amoxicillin as the preferred first-line treatment for Group A Streptococcal pharyngitis in children at 50 mg/kg once daily (maximum 1,000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days. 2, 1
For your 25 kg patient, this translates to:
The practical dosing for this child is therefore 1,000 mg once daily OR 500 mg twice daily for 10 days. 2, 1
Critical Treatment Duration
Complete the full 10-day course regardless of symptom resolution to prevent acute rheumatic fever, as recommended by the American Academy of Family Physicians. 1, 3
Treatment should continue for at least 10 days for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever. 3
Common Pitfall to Avoid
Do NOT use the older 40 mg/kg/day dosing regimen for strep throat—this outdated dosing is less effective for clinical and bacteriologic cure. 1, 4
The current evidence shows that 50 mg/kg once daily or 25 mg/kg twice daily provides superior clinical cure rates (87.9% vs 70.9%) and bacteriologic cure rates (79.3% vs 54.5%) compared to lower-dose regimens. 4
When to Consider Alternatives
Reserve amoxicillin/clavulanate (Augmentin) for treatment failures or chronic carriers who have failed first-line amoxicillin therapy. 2, 1
For penicillin-allergic patients, consider cephalexin, clindamycin, or azithromycin as alternatives. 2, 1
Be aware that macrolides like azithromycin may have reduced efficacy in areas with high clarithromycin resistance among Group A Streptococcus. 5