Antibiotic Treatment for Group A Streptococcal Tonsillitis

First-Line Treatment for Non-Allergic Patients

The American Academy of Pediatrics and the Infectious Diseases Society of America recommend penicillin V or amoxicillin for 10 days as the first-line treatment for Group A beta-hemolytic streptococcal (GABHS) tonsillitis, with penicillin V dosed at 250 mg twice or three times daily in children and 250 mg four times daily or 500 mg twice daily in adolescents and adults, due to its proven efficacy, narrow spectrum, safety profile, and low cost, with no documented penicillin resistance in GABHS anywhere in the world 1, 2, 3
Penicillin V (oral) is recommended for children at 250 mg twice or three times daily and for adolescents and adults at 250 mg four times daily or 500 mg twice daily for 10 days, with strong, high-quality evidence supporting its efficacy 1, 2
Amoxicillin (oral) is recommended at 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days, with strong, high-quality evidence supporting its efficacy, and is often preferred in children due to better taste acceptance 1, 2, 3
Benzathine penicillin G (intramuscular) is recommended as a single dose of 600,000 units for patients under 27 kg and 1,200,000 units for patients 27 kg or greater, with strong, high-quality evidence supporting its efficacy 1, 2

For non-immediate (non-anaphylactic) penicillin allergy, first-generation cephalosporins are the preferred first-line alternatives, with strong, high-quality evidence supporting their efficacy, and cephalexin is recommended at 20 mg/kg per dose twice daily (maximum 500 mg/dose) for 10 days, and adults receive 500 mg twice daily for 10 days 1, 2, 4, 5
For immediate/anaphylactic penicillin allergy, all beta-lactam antibiotics must be avoided due to up to 10% cross-reactivity risk with cephalosporins, and clindamycin is the preferred alternative at 7 mg/kg per dose three times daily (maximum 300 mg/dose) for 10 days, with strong, moderate-quality evidence supporting its efficacy 1, 2, 4, 5

Macrolide resistance among GABHS varies geographically and temporally, with approximately 5-8% resistance in the United States, making clindamycin or first-generation cephalosporins preferred alternatives in areas with high macrolide resistance, and local resistance patterns should be considered before prescribing macrolides 4, 5

Do not use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to the 10% cross-reactivity risk, and do not prescribe shorter courses than recommended (except azithromycin's 5-day regimen) as this leads to treatment failure and increased risk of acute rheumatic fever 1, 2, 4, 5, 3

Acetaminophen or NSAIDs (such as ibuprofen) should be considered for moderate to severe symptoms or high fever, and corticosteroids are not recommended as adjunctive therapy 4, 3, 5

For patients who fail penicillin therapy, retreatment with the same regimen can be considered if compliance was adequate, or intramuscular benzathine penicillin G if compliance is questionable, and clindamycin or amoxicillin-clavulanate are particularly effective following penicillin failures due to their ability to eradicate BLPB and superior intracellular penetration 3, 5

The American Academy of Pediatrics recommends penicillin V or amoxicillin for 10 days as the first-line treatment for Group A beta-hemolytic streptococcal (GABHS) pharyngitis/tonsillitis due to proven efficacy, narrow spectrum, safety profile, low cost, and the absence of any documented penicillin resistance in GABHS worldwide 6
A systematic review found no evidence of differing efficacy between azithromycin and comparator agents (including penicillin) for acute pharyngitis in adults and children, with a strength of evidence rated as moderate 6, 7

The Infectious Diseases Society of America recommends azithromycin 12 mg/kg once daily for 5 days as an alternative treatment for patients who cannot tolerate first-line beta-lactam therapy, with a strength of evidence rated as high 6
A study comparing two azithromycin dosages found that 20 mg/kg/day for 3 days (total 60 mg/kg) achieved 94.2% bacteriologic eradication, demonstrating the importance of optimal dosing 6