What is the first-line treatment for strep throat in adults?

First-Line Treatment for Strep Throat in Adults

The first-line treatment for strep throat (Group A Streptococcal pharyngitis) in adults is penicillin V or amoxicillin for a full 10-day course. 1

Diagnosis Before Treatment

Before initiating treatment, proper diagnosis is essential:

• Use Centor Criteria to assess likelihood of Group A Streptococcal (GAS) infection:

  • Fever
  • Tonsillar exudates
  • Tender anterior cervical lymphadenopathy
  • Absence of cough 1

• Testing recommendations:

  • 0-2 Centor criteria: No testing needed (unlikely GAS)
  • 3-4 Centor criteria: Perform rapid antigen detection test (RADT) 1
  • In adults, negative RADT does not require throat culture confirmation 1

First-Line Antibiotic Treatment

Recommended Medications and Dosages

• Penicillin V: 500 mg 2-3 times daily for 10 days 1
• Amoxicillin: 25 mg/kg twice daily (maximum 500 mg per dose) or 50 mg/kg once daily (maximum 1000 mg) for 10 days 1

Important: Complete the full 10-day course to prevent treatment failure, rheumatic fever, and bacterial resistance 1

Alternative Treatments for Penicillin-Allergic Patients

For patients with penicillin allergy:

• Non-anaphylactic penicillin allergy: First-generation cephalosporins (e.g., cephalexin 20 mg/kg twice daily, maximum 500 mg per dose) for 10 days 1, 2

• Severe penicillin allergy:

  • Clindamycin: 7 mg/kg three times daily (maximum 300 mg per dose) for 10 days 1
  • Macrolides (e.g., azithromycin): 12 mg/kg once daily (maximum 500 mg) for 5 days 1

Caution: Macrolides should be reserved for penicillin-allergic patients due to increasing resistance patterns 1, 2

Symptomatic Treatment

In addition to antibiotics, symptomatic relief measures include:

• NSAIDs or acetaminophen for pain and fever
• Warm salt water gargles
• Throat lozenges 1

Treatment Monitoring and Follow-up

• Patients should seek medical attention if symptoms persist or worsen after 48-72 hours of antibiotic therapy 1
• If treatment failure occurs, reassess diagnosis and consider alternative antibiotics 1

Common Pitfalls to Avoid

1. Incomplete antibiotic course: Failure to complete the full 10-day course can lead to treatment failure and risk of rheumatic fever 1

2. Unnecessary antibiotic use: Most sore throats (>60%) are viral and do not require antibiotics 1, 2

3. Macrolide overuse: Using azithromycin or clarithromycin as first-line treatment despite significant resistance in some parts of the US 2

4. Steroid use: Steroids are not recommended for symptomatic treatment of strep throat 2

5. Failure to consider local resistance patterns: Local antibiotic resistance should inform antibiotic selection 1

The evidence strongly supports penicillin and amoxicillin as first-line treatments for streptococcal pharyngitis in adults, with a full 10-day course being essential for proper eradication of the infection and prevention of complications.