Amoxicillin Dosing for Strep Throat in a 32-Pound Child
For a 32-pound (14.5 kg) child with strep throat, give amoxicillin 725 mg once daily OR 363 mg twice daily for 10 days. 1
Recommended Dosing Calculation
The American Academy of Family Physicians recommends amoxicillin as first-line treatment at 50 mg/kg once daily (maximum 1,000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose). 1
For your 32-pound (14.5 kg) child:
- Once-daily dosing: 50 mg/kg × 14.5 kg = 725 mg once daily 1
- Twice-daily dosing: 25 mg/kg × 14.5 kg = 363 mg twice daily 1
Practical Dispensing Considerations
Since amoxicillin suspension comes in 125 mg/5 mL or 250 mg/5 mL concentrations 2:
- For once-daily: Give approximately 14.5 mL of 250 mg/5 mL suspension once daily
- For twice-daily: Give approximately 7.3 mL of 250 mg/5 mL suspension twice daily
Critical Treatment Duration
Complete the full 10-day course regardless of symptom improvement to prevent acute rheumatic fever. 3, 2 This is non-negotiable even when the child feels better after 2-3 days. 1
Administration Instructions
Give amoxicillin at the start of a meal to minimize gastrointestinal side effects. 2 The suspension can be mixed with formula, milk, fruit juice, water, or cold drinks if needed, but must be taken immediately after mixing. 2
Common Pitfalls to Avoid
Do not use the older 40 mg/kg/day dosing regimen that was standard in the 1990s—this lower dose has inferior bacteriologic cure rates (54.5% vs 79.3%) compared to higher dosing. 1, 4 The once-daily 50 mg/kg or twice-daily 25 mg/kg regimens are now standard based on more recent evidence. 5
Do not prescribe amoxicillin/clavulanate (Augmentin) as first-line therapy. Reserve this for treatment failures or chronic carriers who have failed standard amoxicillin. 6, 1
When to Consider Alternatives
For penicillin allergy (true Type I hypersensitivity), use cephalexin, clindamycin, or azithromycin instead. 3, 1 However, differentiate true allergic reactions from common side effects like diarrhea or rash, as many children labeled "penicillin allergic" can actually tolerate amoxicillin. 3
Storage and Stability
After reconstitution, shake the suspension well before each use and keep the bottle tightly closed. 2 Refrigeration is preferable but not required. 2 Discard any unused suspension after 14 days. 2
Follow-Up Considerations
Reassess if symptoms worsen or fail to improve after 48-72 hours of therapy, as this may indicate treatment failure requiring alternative antibiotics or further evaluation. 3, 7