What does the Centers for Disease Control and Prevention (CDC) recommend for the treatment of streptococcal pharyngitis?

CDC Recommendations for Streptococcal Pharyngitis Treatment

The CDC recommends intramuscular benzathine penicillin G as a single dose (600,000 units if <27 kg; 1,200,000 units if ≥27 kg) when adherence to oral therapy is uncertain, or oral penicillin V/amoxicillin for 10 days as first-line treatment for group A streptococcal pharyngitis. 1

First-Line Treatment Options

The CDC endorses the following evidence-based regimens for streptococcal pharyngitis:

Oral Therapy (When Compliance Expected)

• Penicillin V: 250 mg four times daily OR 500 mg twice daily for 10 days in adolescents and adults 2, 1
• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) for 10 days, often preferred in children due to better palatability and once-daily dosing 2, 1, 3
• Amoxicillin alternative dosing for adults: 500 mg twice daily for 10 days 4

Intramuscular Therapy (When Compliance Uncertain)

• Benzathine penicillin G: Single dose ensures compliance when adherence to oral therapy is questionable 1
  • 600,000 units if weight <27 kg
  • 1,200,000 units if weight ≥27 kg

Critical Treatment Duration Requirement

The full 10-day course is absolutely essential for all antibiotics (except azithromycin) to achieve maximal pharyngeal eradication and prevent acute rheumatic fever. 2, 1, 3 This requirement is explicitly stated in FDA labeling: "It is recommended that there be at least 10 days' treatment for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever." 3

• Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 5
• Shortening the course by even a few days results in appreciable increases in treatment failure rates 1

Penicillin-Allergic Patients

The CDC provides clear guidance based on allergy type:

Non-Immediate (Non-Anaphylactic) Penicillin Allergy

• First-generation cephalosporins are preferred: Cephalexin 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days 2, 1
• Cross-reactivity risk is only 0.1% in patients with non-severe, delayed penicillin reactions 5

Immediate/Anaphylactic Penicillin Allergy

All beta-lactam antibiotics must be avoided due to up to 10% cross-reactivity risk. 2, 1, 5

• Clindamycin (preferred): 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days 2, 1

  • Approximately 1% resistance rate among Group A Streptococcus in the United States 1, 5
  • Highly effective even in chronic carriers 1

• Azithromycin (alternative): 12 mg/kg once daily (maximum 500 mg) for 5 days 2, 1

  • Only antibiotic requiring just 5 days due to prolonged tissue half-life 1, 5
  • Macrolide resistance is 5-8% in the United States 1, 5

• Clarithromycin (alternative): 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days 2, 1

Why Penicillin/Amoxicillin Remains First-Line

• Proven efficacy and safety: Penicillin-resistant Group A Streptococcus has never been documented anywhere in the world 2, 1, 4
• Narrow spectrum: Minimizes selection pressure for antibiotic-resistant flora 2
• Low cost: Most economical option 2, 1, 4

Common Pitfalls to Avoid

• Do NOT use trimethoprim-sulfamethoxazole (Bactrim): Does not eradicate Group A Streptococcus and should never be used for streptococcal pharyngitis 2, 5
• Do NOT use tetracyclines: High prevalence of resistant strains 2
• Do NOT use older fluoroquinolones (ciprofloxacin): Limited activity against Group A Streptococcus 2
• Do NOT prescribe cephalosporins to patients with immediate/anaphylactic penicillin reactions: 10% cross-reactivity risk makes this dangerous 1, 5
• Do NOT shorten treatment courses below 10 days (except azithromycin's 5-day regimen): Dramatically increases treatment failure and rheumatic fever risk 1, 5
• Do NOT use azithromycin as first-line when penicillin can be used: Reserve for true penicillin allergy due to resistance concerns 1, 4

Adjunctive Therapy

• Acetaminophen or NSAIDs (ibuprofen): Recommended for moderate to severe symptoms or high fever 1, 5
• Avoid aspirin in children: Risk of Reye syndrome 1, 5
• Corticosteroids are NOT recommended 1, 5

Special Populations

Healthcare Worker Carriage Eradication

For pharyngeal carriage in healthcare workers, the CDC recommends:

• Oral penicillin V 500 mg four times daily for 10 days, OR
• Amoxicillin 500 mg three times daily for 10 days, OR
• Clindamycin 300 mg four times daily for 10 days (if first-line penicillin therapy fails), OR
• Azithromycin (maximum 500 mg once daily) for 3 days 1

Treatment Failures and Chronic Carriers

• If treatment fails despite adequate compliance, retreatment with the same regimen is acceptable if compliance was good 1
• Clindamycin 20-30 mg/kg per day in three doses (maximum 300 mg per dose) for 10 days is effective for chronic carriers or multiple failures 1
• Chronic carriers generally do not require treatment as they are unlikely to spread infection or develop complications 1, 5