What is the recommended treatment for bacterial tonsillitis?

Treatment of Bacterial Tonsillitis

Penicillin or amoxicillin for 10 days is the first-line treatment for bacterial tonsillitis, with specific alternative options for patients with penicillin allergies. 1

Diagnosis and Assessment

Before initiating treatment, proper diagnosis is essential:

• Use Centor Criteria to assess likelihood of bacterial infection:

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

• Patients with 0-2 Centor criteria are unlikely to have Group A Streptococcal (GAS) infection

• Patients with 3-4 criteria should undergo Rapid Antigen Detection Test (RADT) and/or throat culture 1

First-Line Treatment

For confirmed bacterial tonsillitis:

• Penicillin V: 500 mg 2-3 times daily for adults; 250 mg 2-3 times daily for children for 10 days 1
• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily for 10 days 1

The 10-day duration is critical because:

• The pharynx is a challenging site for antibiotic penetration
• Shorter courses increase risk of relapse and complications like acute rheumatic fever or glomerulonephritis 1

Alternative Treatments for Penicillin-Allergic Patients

For patients with non-anaphylactic penicillin allergy:

• First-generation cephalosporins for 10 days 1

For patients with anaphylactic penicillin allergy:

• Clindamycin: 300-450 mg orally three times daily for 10 days 1
• Azithromycin: 12 mg/kg once daily (max 500 mg) for 5 days 1, 2
• Clarithromycin for 10 days 1

Caution: Significant resistance to azithromycin and clarithromycin exists in some parts of the United States 1

Azithromycin Considerations

When using azithromycin:

• Clinical success rates of 94-98% have been reported 2
• Common side effects include diarrhea/loose stools (5.9%), vomiting (2.1%) 2
• Note that penicillin remains the drug of choice for preventing rheumatic fever 2

Treatment Failures

If initial therapy fails:

• Consider beta-lactamase-producing bacteria "shielding" the streptococci 1
• Penicillin treatment failures occur in 5-35% of cases 1
• Consider alternative agents but avoid fluoroquinolones due to resistance concerns 1

Supportive Care

In addition to antibiotics:

• Acetaminophen or NSAIDs (not aspirin in children) for pain and fever 1
• Cold liquids or ice chips, gargling with cold water 1
• Avoid hot liquids, spicy foods, and hard foods that may irritate the throat 1

Return to School/Work

• Patients should complete at least 24 hours of antibiotics before returning to school or work to reduce transmission risk 1

Important Considerations

• Bacterial tonsillitis requires appropriate antibiotic therapy to prevent complications
• Clinical features alone cannot reliably differentiate GAS from viral pharyngitis 1
• Penicillin failure rates have increased over time, possibly due to poor compliance with the 10-day regimen 3
• Patients should complete the full course of antibiotics even if symptoms improve

Remember that proper identification and adequate antibiotic treatment of GAS pharyngitis is essential for primary prevention of acute rheumatic fever 1.