What is the treatment for acute pharyngitis?

Treatment of Acute Pharyngitis

Penicillin or amoxicillin for 10 days is the first-line treatment for Group A Streptococcal (GAS) pharyngitis, which is the only common form of acute pharyngitis requiring antibiotic therapy. 1

Diagnosis Before Treatment

Proper diagnosis is essential before initiating treatment, as most cases of acute pharyngitis are viral in origin and do not require antibiotics.

Diagnostic Approach:

• Use Centor Criteria to guide testing decisions 1:

  1. Tonsillar exudates
  2. Tender anterior cervical lymph nodes
  3. Lack of cough
  4. Fever

• Testing recommendations:

  • Patients with 0-1 criteria: No testing or antibiotics needed
  • Patients with 2-4 criteria: Test with Rapid Antigen Detection Test (RADT) and/or throat culture 1, 2
  • Children <3 years: Testing generally not recommended unless specific risk factors exist 3

Antibiotic Treatment for GAS Pharyngitis

First-line Treatment:

• Penicillin V:

  • Children: 250 mg 2-3 times daily for 10 days
  • Adults: 500 mg 2-3 times daily for 10 days 1, 4

• Amoxicillin:

  • 50 mg/kg once daily (maximum 1000 mg) or
  • 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1

For Penicillin-Allergic Patients:

• Non-anaphylactic allergy: First-generation cephalosporins for 10 days
• Anaphylactic allergy:
  • Clindamycin: 300-450 mg orally three times daily for 10 days
  • Azithromycin: 12 mg/kg once daily (max 500 mg) for 5 days 1, 5

For Treatment Failures:

• Consider one of the following 1:
  • Clindamycin
  • Amoxicillin-clavulanate
  • Narrow-spectrum cephalosporin
  • Penicillin with rifampin

Rationale for Treatment

The primary objectives of treatment are 1, 3:

1. Prevention of acute rheumatic fever
2. Prevention of suppurative complications (peritonsillar abscess, cervical lymphadenitis)
3. Reduction of symptom duration and severity
4. Decrease in infectivity to reduce transmission
5. Minimization of adverse effects from inappropriate antimicrobial therapy

Symptomatic Relief

In addition to antibiotics for confirmed GAS pharyngitis, the following symptomatic measures are recommended 1:

• Analgesics/antipyretics (acetaminophen or NSAIDs) for pain and fever
• Throat lozenges and warm salt water gargles
• Cold liquids or ice chips
• Avoiding irritating foods and beverages

Important Considerations

1. Complete the full course: A full 10-day course of beta-lactam antibiotics is mandatory to prevent acute rheumatic fever, with the exception of azithromycin (5-day course) 1

2. Return to school/work: Patients should complete at least 24 hours of antibiotics before returning to school or work to reduce transmission risk 1

3. Treatment failures: Penicillin treatment failures occur in 5-35% of cases, possibly due to beta-lactamase-producing bacteria "shielding" the streptococci 1

4. Non-GAS pharyngitis: Both group C and group G β-hemolytic streptococci can cause acute pharyngitis with clinical features similar to GAS, but acute rheumatic fever has not been described as a complication of these infections 3

5. Viral pharyngitis: The vast majority of children and adults with acute pharyngitis have a viral etiology and do not need antibiotic treatment 3

Remember that overuse of antibiotics contributes to antimicrobial resistance, so confirming GAS infection before treatment is crucial 6, 2.