Treatment of Streptococcal Pharyngitis in a 6-Year-Old
For a 6-year-old with strep throat, prescribe amoxicillin 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily for 10 days, or alternatively penicillin V 250 mg twice daily for 10 days. 1
First-Line Antibiotic Selection
Amoxicillin is the preferred first-line agent over penicillin V because it:
- Has superior palatability in suspension form, improving adherence 1
- Can be dosed once daily (50 mg/kg, maximum 1000 mg), which significantly enhances compliance 1
- Demonstrates equivalent or superior bacteriologic eradication rates compared to penicillin V 2
- Is relatively inexpensive and has a narrow spectrum of activity 1
Penicillin V remains an acceptable alternative at 250 mg twice daily for children, though it requires more frequent dosing and tastes worse 1
Critical Treatment Duration
A full 10-day course is mandatory for children 6 years old to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever 1. The guideline evidence is clear: children younger than 6 years and those with severe symptoms require standard 10-day therapy 1. While 7-day courses may be adequate for children 2-5 years with mild disease, a 6-year-old falls into the age group requiring the full 10 days 1.
Do not shorten the antibiotic course even though symptoms typically resolve within 3-4 days—the primary goal is preventing rheumatic fever, not just symptomatic relief 1, 3, 4.
Treatment for Penicillin Allergy
Non-Anaphylactic Penicillin Allergy
First-generation cephalosporins are the preferred alternatives:
- Cephalexin 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days 1, 3, 4
- Cefadroxil 30 mg/kg once daily (maximum 1 gram) for 10 days 1, 3, 4
These have strong, high-quality evidence for efficacy and superior bacteriologic eradication compared to penicillin 1, 3, 4.
Immediate/Anaphylactic Penicillin Allergy
Avoid all beta-lactams (including cephalosporins) due to up to 10% cross-reactivity risk 1, 3, 4. Use instead:
Clindamycin 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days is the preferred option:
- Strong, moderate-quality evidence for efficacy 3, 4
- Highly effective at eradicating streptococci, even in chronic carriers 3, 4
- Only ~1% resistance rate in the United States 3, 4
Azithromycin 12 mg/kg once daily (maximum 500 mg) for 5 days is an acceptable alternative:
- Only macrolide requiring just 5 days due to prolonged tissue half-life 1, 3, 4, 5
- However, macrolide resistance is 5-8% in the United States and varies geographically 3, 4, 6, 7
- Should not be used as first-line therapy—reserve for true penicillin-allergic patients 3, 4
Clarithromycin 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days is another option, but shares the same resistance concerns as azithromycin 1, 3, 4, 7.
Diagnostic Confirmation
Always confirm the diagnosis with rapid antigen detection test (RADT) or throat culture before prescribing antibiotics 1, 3, 6. A positive RADT is diagnostic and does not require backup culture 1, 3. However, in children and adolescents with negative RADT, perform a backup throat culture because the incidence of strep pharyngitis and risk of rheumatic fever are higher in this age group 1, 3.
Do not test or treat if viral features predominate (cough, rhinorrhea, hoarseness, conjunctivitis, oral ulcers) 1, 6.
Adjunctive Symptomatic Treatment
- Acetaminophen or ibuprofen for moderate to severe symptoms or high fever 1, 3, 4
- Never use aspirin in children due to Reye syndrome risk 1, 3, 4
- Corticosteroids are not recommended 1, 3, 4
Common Pitfalls to Avoid
Do not prescribe antibiotics without diagnostic confirmation—60% or more adults with sore throat receive antibiotics, but only 10% actually have strep 6. This leads to unnecessary antibiotic exposure and resistance.
Do not use trimethoprim-sulfamethoxazole (Bactrim)—it has 50% resistance rates against Group A Streptococcus and is not recommended 3.
Do not assume all penicillin-allergic patients need to avoid cephalosporins—only those with immediate/anaphylactic reactions should avoid them 1, 3, 4.
Do not prescribe macrolides (azithromycin, clarithromycin) as first-line therapy in areas with high resistance rates or without considering local resistance patterns 3, 4, 6, 7.
Follow-Up Considerations
Routine post-treatment testing is not recommended for asymptomatic patients who completed therapy 1, 3, 4. Reevaluate only if:
- Symptoms worsen after appropriate antibiotic initiation 6
- Symptoms persist 5 days after starting treatment 6
- Patient has personal or family history of rheumatic fever 1, 3
Patients are no longer contagious after 24 hours of antibiotic therapy and can return to normal activities 1.