What is the recommended treatment, dose, and frequency for a patient with tonsillitis, assuming no severe underlying conditions or allergies?

Treatment of Tonsillitis: Antibiotic Selection, Dosing, and Duration

For confirmed bacterial (Group A Streptococcus) tonsillitis, penicillin V administered orally for 10 days remains the first-line treatment, with amoxicillin for 10 days as an acceptable alternative. 1, 2

Diagnostic Confirmation Required

Before initiating antibiotics, bacterial tonsillitis must be confirmed through rapid antigen detection testing (RADT) and/or throat culture for Group A Streptococcus (GAS). 1, 2 Bacterial tonsillitis characteristically presents with:

• Sudden onset of sore throat
• Fever >38°C (100.4°F)
• Tonsillar exudates
• Tender anterior cervical lymphadenopathy
• Absence of cough 1, 3

Do not initiate antibiotics without microbiological confirmation, as 70-95% of tonsillitis cases are viral and do not benefit from antibiotics. 4

First-Line Antibiotic Therapy

Penicillin V (Preferred)

• Dosage for adults and children ≥40 kg: 500 mg orally twice daily OR 250 mg orally three times daily for 10 days 5, 1
• Dosage for children <40 kg: 25 mg/kg/day divided twice daily OR 20 mg/kg/day divided three times daily for 10 days 6
• The 10-day duration is mandatory to maximize bacterial eradication and prevent complications like rheumatic fever 1, 2

Amoxicillin (Alternative First-Line)

• Dosage for adults and children ≥40 kg: 500 mg orally twice daily OR 250 mg orally three times daily for 10 days 6
• Dosage for children <40 kg: 25 mg/kg/day divided twice daily OR 20 mg/kg/day divided three times daily for 10 days 6
• Should be taken at the start of meals to minimize gastrointestinal intolerance 6

Important caveat: Short courses of penicillin (less than 10 days) are less effective for GAS eradication and increase the risk of treatment failure. 2, 3 While some studies suggest 5-day courses of certain antibiotics may be adequate, the standard 10-day course remains the guideline recommendation to prevent rheumatic fever. 5, 1

Penicillin-Allergic Patients

Non-Anaphylactic Allergy

First-generation cephalosporins for 10 days: 2

• Cephalexin
• Cefadroxil

Anaphylactic Allergy

Alternative antibiotics for 10 days: 2

• Clindamycin: 20-30 mg/kg/day in 3 divided doses (maximum 300 mg/dose) 2
• Azithromycin: Dosing per standard protocols
• Clarithromycin: Dosing per standard protocols
• Erythromycin: 30-50 mg/kg/day in divided doses (adults: 250 mg four times daily) for at least 10 days 7

Treatment Failures and Recurrent Infections

If symptoms return within 2 weeks of completing standard therapy, consider alternative regimens: 2

• Clindamycin: 20-30 mg/kg/day in 3 divided doses for 10 days
• Amoxicillin-clavulanate: 40 mg amoxicillin/kg/day in 3 divided doses (maximum 2000 mg amoxicillin/day) for 10 days
• Penicillin V with rifampin: Penicillin V 50 mg/kg/day in 4 doses for 10 days plus rifampin 20 mg/kg/day in 1 dose for the last 4 days 2

Common pitfall: Recurrent positive GAS tests may indicate chronic carriage with intercurrent viral infections rather than repeated bacterial infections. Up to 20% of asymptomatic school-age children may be GAS carriers during winter and spring. 2

Supportive Care (Essential for All Patients)

Regardless of antibiotic use, all patients require symptomatic management: 5, 2

• Ibuprofen or acetaminophen for pain and fever control
• Adequate hydration
• Warm salt water gargles (for patients old enough to perform)

Role of Corticosteroids

A single dose of corticosteroids in conjunction with antibiotic therapy may benefit adults with severe or high Centor scoring sore throat, but no significant benefit has been demonstrated in children. 5 This should be reserved for severe cases only.

When to Consider Tonsillectomy

Tonsillectomy is not recommended solely to reduce the frequency of GAS pharyngitis. 1, 2 Consider tonsillectomy only when meeting Paradise criteria with proper documentation: 1

• ≥7 documented episodes in the past year, OR
• ≥5 episodes per year for 2 consecutive years, OR
• ≥3 episodes per year for 3 consecutive years

Each documented episode must include sore throat plus at least one of: temperature ≥38.3°C, cervical adenopathy, tonsillar exudate, or positive GAS test. 2

Critical Pitfalls to Avoid

• Never initiate antibiotics without confirming GAS infection through testing 1, 3
• Never use shorter courses than 10 days for standard penicillin or amoxicillin therapy 1, 2
• Never use broad-spectrum antibiotics when narrow-spectrum penicillins are effective for confirmed GAS 1
• Never perform follow-up throat cultures for asymptomatic patients who completed appropriate therapy 2, 3
• Never treat based on ASO titers, as they reflect past immunologic response, not current infection 2