What is the recommended treatment for acute pharyngitis, especially when a bacterial cause is suspected?

Treatment of Acute Pharyngitis

For acute pharyngitis with suspected bacterial cause, penicillin or amoxicillin is the recommended first-line treatment due to their proven efficacy, safety, narrow spectrum, and low cost. 1, 2

Diagnosis Before Treatment

Before initiating treatment, it's important to determine if the pharyngitis is likely bacterial:

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

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

• Testing recommendations:

  • Patients with 0-1 criteria: No testing or antibiotics needed
  • Patients with 2+ criteria: Perform rapid antigen detection test (RADT) or throat culture
  • Do not test children <3 years old (GAS pharyngitis uncommon in this age group) 1

First-Line Treatment for GAS Pharyngitis

For confirmed GAS pharyngitis:

Adults:

• Penicillin V: 250 mg orally 3-4 times daily OR 500 mg twice daily for 10 days 1
• Amoxicillin: 500 mg twice daily for 10 days OR 1000 mg once daily for 10 days 1, 2, 3

Children:

• Penicillin V: 250 mg 2-3 times daily for 10 days 1
• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) for 10 days 1, 3

Parenteral Option (for compliance concerns):

• Benzathine penicillin G: 1.2 million units IM as a single dose 1

Treatment for Penicillin-Allergic Patients

Non-anaphylactic allergy:

• First-generation cephalosporins for 10 days 1

Anaphylactic allergy:

• Clindamycin: Adults: 600 mg/day in 2-4 divided doses for 10 days; Children: 20-30 mg/kg/day divided for 10 days 1
• Clarithromycin: 250 mg twice daily for 10 days 1
• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 4

Caution: Macrolide resistance in GAS varies geographically and should be considered 1

Duration of Treatment

A full 10-day course is recommended for all beta-lactams (penicillin, amoxicillin) to ensure bacterial eradication and prevent complications like rheumatic fever 1, 3. The only exception is azithromycin, which is given for 5 days 1, 4.

Adjunctive Therapy

• Acetaminophen or NSAIDs for pain relief and fever reduction 1
• Avoid aspirin in children due to risk of Reye syndrome 1
• Corticosteroids are not recommended 1

Common Pitfalls to Avoid

1. Treating without testing: Most pharyngitis cases (70-90%) are viral, not bacterial 5, 6. Avoid unnecessary antibiotics.

2. Using broad-spectrum antibiotics as first-line: Despite some evidence that cephalosporins may provide higher bacterial eradication rates 7, penicillin/amoxicillin remain first-line due to narrow spectrum, low cost, and no documented resistance 1.

3. Short treatment courses: Despite newer antibiotics claiming efficacy with shorter courses, the standard 10-day course is still recommended for beta-lactams to prevent rheumatic fever 1.

4. Testing or treating asymptomatic household contacts: This is not routinely recommended 1.

5. Follow-up cultures: Not routinely needed after treatment if symptoms resolve 1.

Management of Recurrent Episodes

For patients with multiple recurrent episodes of GAS pharyngitis:

• Clindamycin: 20-30 mg/kg/day for children or 600 mg/day for adults in 2-4 divided doses for 10 days 1
• Amoxicillin-clavulanate: 40 mg/kg/day in 3 divided doses for 10 days (max 750 mg amoxicillin/day) 1
• Benzathine penicillin G with or without rifampin 1

Tonsillectomy may be considered for very frequent recurrences (≥7 episodes in past year or ≥5 episodes/year for 2 consecutive years) 2.