Amoxicillin Dosing for Strep Throat in a 5-Year-Old, 60-Pound Child
For a 5-year-old child weighing 60 pounds (27.3 kg) with strep throat, give amoxicillin 50 mg/kg/day divided into 2 doses for 10 days, which equals approximately 680 mg twice daily or 13.6 mL of the 250 mg/5 mL suspension twice daily. 1
Weight-Based Calculation
- The child weighs 60 pounds = 27.3 kg 1
- For Group A Streptococcal pharyngitis (strep throat), the Infectious Diseases Society of America and American Heart Association recommend 50-75 mg/kg/day divided into 2 doses 1
- Using 50 mg/kg/day: 27.3 kg × 50 mg/kg = 1,365 mg total daily dose 1
- Divided into 2 doses = 680 mg per dose, twice daily 1
Practical Dosing with 250 mg/5 mL Suspension
- 680 mg per dose ÷ 50 mg/mL = 13.6 mL twice daily 1
- Alternatively, you can round to 14 mL twice daily for practical administration 1
- This provides approximately 700 mg per dose, which falls within the recommended 50-75 mg/kg/day range 1
Treatment Duration
- Complete the full 10-day course to prevent acute rheumatic fever, even if symptoms resolve earlier 1, 2
- The American Academy of Family Physicians emphasizes that at least 10 days of treatment is essential for Group A Streptococcal infections to prevent complications 3
- The child becomes non-contagious after 24 hours of antibiotic therapy 1
Administration Instructions
- Give amoxicillin at the start of a meal to minimize gastrointestinal side effects 2
- Shake the suspension well before each use 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
Maximum Dose Considerations
- While the calculated dose is 680 mg twice daily, the American Academy of Family Physicians notes that individual doses should not exceed 1,000 mg per dose for strep throat 1
- The absolute maximum daily dose of amoxicillin is 4,000 mg/day regardless of weight 4, 2
- This child's calculated dose (1,360-1,400 mg/day) is well below these limits 1
Clinical Monitoring
- Clinical improvement should be evident within 48-72 hours 1
- If no improvement occurs within this timeframe, reevaluation is necessary 1
- Common adverse effects include gastrointestinal disturbances (diarrhea, nausea, vomiting) and rash 1
Important Pitfalls to Avoid
- Do not use once-daily dosing of penicillin for strep throat, as it is associated with 12 percentage points lower cure rates compared to more frequent dosing 5
- Do not shorten the treatment duration below 10 days for strep throat, as this is critical for preventing rheumatic fever 1, 2
- Amoxicillin is preferred over penicillin V due to better taste and improved adherence with twice-daily dosing 1