Maximum Dose of Amoxicillin for Strep Throat in a 14-Year-Old
For a 14-year-old child with strep throat, the maximum dose of amoxicillin is 1,000 mg per day when using the once-daily regimen, or 1,000 mg per day (500 mg twice daily) when using the twice-daily regimen, with treatment continued for 10 days. 1, 2
Recommended Dosing Regimens
For Group A Streptococcal pharyngitis (strep throat) in adolescents, the following evidence-based options are available:
Standard dosing: 50 mg/kg once daily with a maximum of 1,000 mg, OR 25 mg/kg twice daily with a maximum of 500 mg per dose, for 10 days 2
Alternative dosing: 50-75 mg/kg/day divided into 2 doses for 10 days 1
At 14 years of age, patients are typically dosed as adults according to most guidelines, which means the maximum daily dose would not exceed 1,000-1,500 mg depending on the regimen selected 3
Critical Treatment Considerations
The full 10-day course must be completed to prevent acute rheumatic fever, even if symptoms resolve earlier 4, 3. This is a non-negotiable requirement for streptococcal pharyngitis.
When Standard Amoxicillin May Be Insufficient
If the patient is a chronic carrier or has failed first-line therapy, amoxicillin/clavulanate (Augmentin) should be considered instead, with a maximum of 2,000 mg per day of the amoxicillin component 2
For treatment failures, the maximum dose of amoxicillin/clavulanate is 40 mg/kg/day of the amoxicillin component divided into three doses, with an absolute maximum of 2,000 mg of amoxicillin per day 2
Clinical Monitoring
Clinical improvement should occur within 24-48 hours of starting treatment 4
If no improvement is seen within 48-72 hours, reassessment is necessary to confirm the diagnosis or consider alternative antibiotics 4
The patient can return to school 12-24 hours after the first dose if afebrile and improved, as 91% of children have non-detectable GAS by this time 5
Important Caveats
Avoid the common pitfall of prescribing inadequate doses. Research demonstrates that amoxicillin at 40 mg/kg/day achieves significantly better clinical cure (87.9% vs 70.9%) and bacteriologic cure (79.3% vs 54.5%) compared to lower-dose penicillin V 6. The declining perception of penicillin effectiveness may be due to inadequate dosing rather than true resistance 6.