What are effective oral treatments for strep throat?

Effective Oral Treatments for Strep Throat

Penicillin V (250 mg twice or three times daily for children, or 500 mg twice daily for adolescents and adults) or amoxicillin (50 mg/kg once daily, maximum 1,000 mg, or 25 mg/kg twice daily, maximum 500 mg per dose) for 10 days are the first-line oral treatments for strep throat due to their proven efficacy, safety, narrow spectrum, and low cost. 1, 2

First-Line Treatment for Non-Allergic Patients

Penicillin V remains the drug of choice because of its narrow spectrum of antimicrobial activity, proven efficacy over four decades, infrequent adverse reactions, and modest cost. 3, 1 The IDSA guidelines provide strong, high-quality evidence supporting this recommendation. 1

Dosing Options:

• Children: Penicillin V 250 mg twice or three times daily for 10 days 1, 4
• Adolescents and adults: Penicillin V 250 mg four times daily OR 500 mg twice daily for 10 days 3, 1
• Amoxicillin alternative: Often preferred in young children due to better palatability of the suspension, with equal efficacy to penicillin V 3, 2, 5
  • 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

Critical Treatment Duration:

A full 10-day course is mandatory for penicillin and amoxicillin to achieve maximal pharyngeal eradication of Group A streptococci and prevent rheumatic fever. 3, 1 Early treatment can reduce symptom duration to less than 24 hours, decrease suppurative complications, and limit disease spread. 6

Treatment for Penicillin-Allergic Patients

The choice depends on the type of allergic reaction:

For Non-Immediate (Non-Anaphylactic) Penicillin Allergy:

First-generation cephalosporins are appropriate alternatives:

• Cephalexin: 20 mg/kg/dose twice daily (maximum 500 mg/dose) for 10 days 1
• Cefadroxil: 30 mg/kg once daily (maximum 1 g) for 10 days 1

These agents should NOT be used in patients with immediate-type hypersensitivity to β-lactam antibiotics due to cross-reactivity risk of up to 10%. 3, 7

For Immediate Penicillin Allergy or Severe Reactions:

Three macrolide/lincosamide options are available with strong, moderate evidence:

1. Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days only 3, 1

   • The only antibiotic requiring less than 10 days due to prolonged tissue half-life 1
   • Important caveat: Resistance to azithromycin varies geographically and temporally; susceptibility testing should be performed 3, 8
   • Data establishing efficacy in preventing rheumatic fever are not available 8
   • More gastrointestinal side effects (16.6%) compared to penicillin (1.7%) 9

2. Clarithromycin: 7.5 mg/kg/dose twice daily (maximum 250 mg/dose) for 10 days 3, 1

3. Clindamycin: 7 mg/kg/dose three times daily (maximum 300 mg/dose) for 10 days 1

Antibiotics to Avoid

Never use sulfonamides or tetracyclines for Group A streptococcal pharyngitis due to high resistance rates and frequent treatment failures. 1 These agents are not recommended by the IDSA guidelines. 3

When Intramuscular Therapy is Preferred

Benzathine penicillin G (intramuscular) should be used instead of oral therapy when compliance with a 10-day oral course is uncertain, particularly in populations with episodic medical care or where rheumatic fever remains prevalent. 3, 1, 6

• Dosing: 600,000 units for patients under 27 kg; 1,200,000 units for patients 27 kg or greater as a single dose 3, 1
• This regimen historically produced the highest cure rates and served as the gold standard through the 1970s 6

Common Pitfalls to Avoid

• Do not use broader-spectrum cephalosporins (like cefpodoxime) as first-line therapy when penicillin or amoxicillin can be used, as this contributes to antimicrobial resistance and increases cost without improving outcomes. 10
• Therapy can be safely delayed up to 9 days after symptom onset and still prevent rheumatic fever, allowing time for culture confirmation before initiating antibiotics. 1
• Compliance is critical: The primary cause of penicillin treatment failure is lack of adherence to the 10-day regimen, with bacteriologic failure rates increasing from 2-10% historically to approximately 30% when compliance is poor. 11
• Perform susceptibility testing for macrolides: Geographic and temporal variation in resistance patterns makes testing essential when using azithromycin or clarithromycin. 3, 8