What is the recommended treatment for strep throat?

Management of Strep Throat

Penicillin V, 500 mg twice daily or 250 mg three times daily for 10 days, is the first-line treatment for streptococcal pharyngitis due to its proven efficacy, safety profile, narrow antimicrobial spectrum, and low cost. 1

Diagnosis and Assessment

• Use Centor Criteria to guide testing decisions:

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

• Patients with 0-2 Centor criteria are unlikely to have Group A Streptococcal (GAS) infection and do not require testing

• Patients with 3-4 criteria should be tested with rapid antigen detection test (RADT) and/or throat culture 1

First-Line Treatment Options

For Non-Allergic Patients:

• Penicillin V:

  • Adults: 500 mg twice daily or 250 mg three times daily for 10 days
  • Children: 250 mg twice daily or 20 mg/kg/day in divided doses every 8 hours for 10 days 2, 1

• Amoxicillin:

  • Adults: 500 mg twice daily or 875 mg twice 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, 3

For Penicillin-Allergic Patients:

• Immediate-type hypersensitivity (anaphylaxis, angioedema, respiratory distress):

  • Erythromycin, clindamycin, or clarithromycin 1

• Non-immediate reactions:

  • First-generation cephalosporins 1

• Azithromycin:

  • 12 mg/kg once daily (max 500 mg) for 5 days 1, 4

Important Treatment Considerations

1. Complete the full course of antibiotics

   • It is essential to complete the full 10-day course (except for azithromycin, which is 5 days) to:
     • Prevent acute rheumatic fever
     • Ensure complete eradication of Group A Streptococcus
     • Reduce risk of treatment failure 1, 3

2. Antibiotics should not be used in patients with less severe presentations (0-2 Centor criteria) to relieve symptoms 2

3. For more severe presentations (3-4 Centor criteria), physicians should discuss the likely benefits with patients, weighing modest benefits against side effects, impact on microbiota, antibiotic resistance, and costs 2

4. Symptomatic relief:

   • NSAIDs or acetaminophen
   • Warm salt water gargles
   • Throat lozenges 1

Treatment Duration

While the traditional 10-day course remains standard, recent research suggests that shorter courses (5-7 days) may be effective in certain cases 5. However, current guidelines still recommend the full 10-day course for penicillin and amoxicillin to prevent complications, particularly acute rheumatic fever 2, 1.

Common Pitfalls and Caveats

1. Antibiotic resistance concerns:

   • Macrolide resistance in Streptococcus pyogenes has increased in some regions, reaching up to 20% in countries like Italy, Spain, and Portugal 1
   • Avoid tetracyclines and sulfonamides due to high levels of resistance 1

2. Treatment failures:

   • Penicillin failure rates have increased over time and may now be approximately 30% 6
   • Causes include:
     • Poor compliance with the 10-day regimen
     • Reexposure to infected family members
     • Copathogenicity
     • Eradication of normal protective pharyngeal flora
     • Penicillin tolerance 6

3. Special populations:

   • Patients with a history of rheumatic fever require continuous antimicrobial prophylaxis to prevent recurrences 1
   • For patients with recurrent tonsillitis, consider tonsillectomy based on the Paradise criteria (≥7 episodes in the preceding year, OR ≥5 episodes in each of the preceding 2 years, OR ≥3 episodes in each of the preceding 3 years) 1

4. Household contacts:

   • Do not require cultures or treatment except in high-risk situations 1

By following these evidence-based guidelines, clinicians can effectively manage streptococcal pharyngitis while minimizing complications and antibiotic resistance.