What is the recommended treatment for strep throat?

Treatment of Strep Throat

Penicillin or amoxicillin is the recommended first-line treatment for strep throat (Group A Streptococcus pharyngitis) due to their proven efficacy, narrow spectrum, low cost, and excellent safety profile. 1

First-Line Antibiotic Options

• Amoxicillin:

  • Adults: 500 mg twice daily or 250 mg three times daily for 10 days
  • Children: 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1, 2

• Penicillin V:

  • Adults: 250 mg three times daily or 500 mg twice daily for 10 days
  • Children: 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours for 10 days 1

The 10-day duration is critical to ensure bacterial eradication and prevent complications such as acute rheumatic fever, regardless of symptom resolution before completion of the full course 1.

Alternative Options for Penicillin-Allergic Patients

For patients with penicillin allergy, the following alternatives are recommended in order of preference:

1. First-generation cephalosporins (for non-anaphylactic penicillin allergy):

   • Cephalexin: Preferred over macrolides due to lower relapse rates 1

2. Clindamycin:

   • Adults: 300-450 mg orally three times daily for 10 days
   • Children: 20-30 mg/kg/day in 2-4 divided doses for 10 days 1

3. Azithromycin:

   • 12 mg/kg once daily (max 500 mg) for 5 days 1
   • Note: There is significant resistance to macrolides in some parts of the US 3

Management of Treatment Failure

If a patient fails initial therapy, consider the following algorithm:

1. Assess compliance with the prescribed regimen
2. Evaluate if the patient is a streptococcal carrier with concurrent viral infection
3. Consider true treatment failure
4. For patients who failed amoxicillin, switch to:
   • Amoxicillin-clavulanate: 40 mg/kg/day in 3 divided doses for 10 days
   • Clindamycin: Effective option for continued treatment failure 1

Diagnosis and Assessment

Use the Centor Criteria to assess the likelihood of GAS pharyngitis:

• Tonsillar exudates
• Tender anterior cervical lymph nodes
• Lack of cough
• Fever

Recommendations based on Centor score:

• Score 3-4: Test using rapid antigen detection tests (RADT) and/or throat culture
• Score 0-2: Unlikely to have GAS infection; testing not required
• Children under 3 years: Testing usually not indicated 1

Symptomatic Relief

While antibiotics are the mainstay of treatment, symptomatic relief measures include:

• Analgesics/antipyretics: Acetaminophen or NSAIDs for moderate to severe symptoms or fever
• Avoid aspirin in children due to risk of Reye syndrome
• Topical remedies: Warm salt water gargles, cold liquids, ice chips
• Maintain adequate hydration 1

Return to School/Work

Patients with strep throat may return to school or work after completing 24 hours of appropriate antibiotic therapy, provided they are feeling well enough and fever has resolved 1.

Important Clinical Considerations

• While some research suggests that cephalosporins may have lower relapse rates than penicillin 4, the most recent guidelines still recommend penicillin or amoxicillin as first-line therapy due to their proven efficacy, safety, and narrow spectrum 1.

• Although older studies have reported increasing penicillin failure rates (up to 30%) 5, current guidelines maintain that penicillin and amoxicillin remain the treatments of choice 1, 3.

• Once-daily amoxicillin (750 mg) has shown similar efficacy to penicillin V given three times daily in some studies 6, which may improve compliance, but the standard recommendation remains twice-daily dosing for amoxicillin 1, 7.