What is the recommended treatment for strep pharyngitis?

Treatment of Streptococcal Pharyngitis

Penicillin or amoxicillin should be used as first-line treatment for streptococcal pharyngitis, administered for a full 10-day course to prevent rheumatic fever and ensure eradication of Group A Streptococcus (GAS). 1

First-Line Treatment Options

Penicillin V

• Children: 250 mg 2-3 times daily for 10 days
• Adolescents/Adults: 250 mg four times daily or 500 mg twice daily for 10 days 1
• BID dosing of penicillin V has been shown to be as effective as more frequent dosing regimens 2

Amoxicillin

• 50 mg/kg once daily (maximum 1,000 mg) for 10 days, OR
• 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1
• Once-daily dosing of amoxicillin has shown comparable efficacy to more frequent dosing 2

Intramuscular Benzathine Penicillin G (single dose)

• <60 lb (27 kg): 600,000 units
• ≥60 lb (27 kg): 1,200,000 units 1
• Particularly useful when compliance with oral therapy is a concern 3

Alternative Treatment for Penicillin-Allergic Patients

For patients with non-anaphylactic penicillin allergy:

• First-generation cephalosporins (e.g., cephalexin): 20 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1

For patients with anaphylactic penicillin allergy:

• Clindamycin: 7 mg/kg three times daily (maximum 300 mg per dose) for 10 days 1
• Clarithromycin: 7.5 mg/kg twice daily (maximum 250 mg per dose) for 10 days 1
• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 4

Important Clinical Considerations

Efficacy and Resistance

• Penicillin resistance in GAS has not been documented worldwide 1
• Macrolide resistance varies geographically, with azithromycin showing clinical success rates of 85% compared to 73% for penicillin in pharyngitis studies 4
• However, penicillin remains the treatment of choice due to its proven efficacy, safety, narrow spectrum, and low cost 5

Duration of Therapy

• The full 10-day course of penicillin or amoxicillin is essential to prevent rheumatic fever 5, 1
• While some studies suggest 5-day therapy with certain cephalosporins may be effective 6, the IDSA guidelines still recommend the standard 10-day course for penicillin/amoxicillin 5

Symptom Management

• Acetaminophen or NSAIDs are recommended for pain relief and fever reduction 1
• Aspirin should be avoided in children due to the risk of Reye syndrome 5
• Corticosteroids are not routinely recommended 5, 1

Follow-Up Recommendations

• Follow-up throat cultures or rapid antigen detection tests (RADT) are not routinely recommended after treatment 5
• Testing or treatment of asymptomatic household contacts is not routinely recommended 5
• Patients should return if symptoms worsen or fail to improve within 48-72 hours of antibiotic initiation 1

Management of Recurrent Episodes

For patients with multiple, recurrent episodes of GAS pharyngitis:

• Consider clindamycin (20-30 mg/kg/day in 3 divided doses for children; 600 mg/day in 2-4 divided doses for adults) for 10 days 5
• Amoxicillin-clavulanic acid may be an alternative option 5
• Tonsillectomy may be considered for patients with severe recurrent infections that don't diminish in frequency over time 5, 1

Common Pitfalls to Avoid

1. Inadequate duration of therapy: Failure to complete the full 10-day course increases the risk of rheumatic fever
2. Inappropriate use of macrolides: Using azithromycin as first-line therapy when penicillin/amoxicillin is more appropriate
3. Unnecessary testing after treatment: Routine post-treatment testing is not recommended
4. Treating asymptomatic carriers: Carriers generally don't require treatment unless specific risk factors exist
5. Once-daily dosing of penicillin V: This has been shown to be less effective than BID or TID dosing 2

By following these evidence-based recommendations, clinicians can effectively treat streptococcal pharyngitis while minimizing complications and preventing rheumatic fever.