What is the recommended treatment for strep (streptococcal) pharyngitis?

Treatment of Streptococcal Pharyngitis

Penicillin or amoxicillin are the first-line antibiotics for streptococcal pharyngitis due to their proven efficacy, safety, narrow spectrum, low cost, and absence of documented resistance worldwide. 1, 2

First-Line Treatment for Non-Allergic Patients

For patients without penicillin allergy, use one of the following regimens:

• Penicillin V (oral) for 10 days 1, 2:

  • Children: 250 mg twice or three times daily 1, 2
  • Adolescents and adults: 250 mg four times daily OR 500 mg twice daily 1, 2

• Amoxicillin (oral) for 10 days as an alternative with equivalent efficacy and better palatability 1, 2:

  • 50 mg/kg once daily (maximum 1,000 mg) OR 25 mg/kg twice daily (maximum 500 mg per dose) 1, 2

• Benzathine penicillin G (intramuscular) as a single dose for patients unlikely to complete oral therapy 1:

  • <60 lb (27 kg): 600,000 units 1
  • ≥60 lb: 1,200,000 units 1

Treatment for Penicillin-Allergic Patients

The choice depends on the type of allergic reaction:

• For non-immediate (non-anaphylactic) penicillin allergy, use first-generation cephalosporins 3, 2:

  • Cephalexin: 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days 3, 2
  • Cefadroxil: 30 mg/kg once daily (maximum 1 g) for 10 days 3

• For immediate/anaphylactic penicillin allergy, use 3, 2:

  • Clindamycin (preferred): 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days 3, 2
  • Clarithromycin: 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days 3
  • Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 3, 4

Critical Treatment Duration

A full 10-day course is mandatory for all antibiotics except azithromycin (5 days) to achieve maximal pharyngeal eradication and prevent acute rheumatic fever. 1, 2 This duration has been the standard for nearly 40 years and remains essential despite the low current incidence of rheumatic fever 5.

Diagnostic Confirmation Before Treatment

• Test patients with sudden onset sore throat, fever, headache, tonsillopharyngeal inflammation/exudates, and tender anterior cervical lymphadenopathy 1
• A positive rapid antigen detection test (RADT) is diagnostic and requires no backup culture 1, 3
• For children and adolescents with negative RADT, perform backup throat culture 1
• Avoid antibiotics for likely viral pharyngitis (presenting with cough, rhinorrhea, hoarseness, or oral ulcers) 1

Adjunctive Symptomatic Therapy

• Use acetaminophen or NSAIDs for moderate to severe symptoms or high fever 1, 3, 2
• Never use aspirin in children due to Reye syndrome risk 1, 3, 2

Management of Recurrent Pharyngitis

For patients with documented recurrent episodes:

• Confirm each episode with RADT or throat culture before treating 3
• Distinguish between true recurrent infections versus chronic carriage with viral infections 3
• Consider retreatment with the same initial agent if compliance was good 1, 2
• For chronic carriers or when compliance is questionable, use 1, 3:
  • Intramuscular benzathine penicillin G 1
  • Clindamycin (7 mg/kg three times daily for 10 days) 1, 3
  • Amoxicillin-clavulanate 1

Tonsillectomy may be considered only for children meeting specific frequency criteria: ≥7 episodes in 1 year, ≥5 episodes per year for 2 years, or ≥3 episodes per year for 3 years, with each episode documented by positive testing 3

Critical Pitfalls to Avoid

• Never use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to 10% cross-reactivity risk 2
• Never use sulfonamides or tetracyclines due to high resistance rates and frequent treatment failures 2
• Be aware that macrolide resistance (azithromycin, clarithromycin) varies geographically and susceptibility testing should be performed 3, 4
• Azithromycin does not have established efficacy data for preventing rheumatic fever 4
• Do not perform routine post-treatment throat cultures in asymptomatic patients 1

Treatment Goals

The primary objectives are preventing acute rheumatic fever, preventing suppurative complications, achieving rapid symptom resolution, decreasing transmission, and minimizing adverse effects 2. Despite increasing bacteriologic failure rates with penicillin noted since the 1970s (now approximately 30% in some studies), penicillin remains the drug of choice based on its proven track record in preventing rheumatic fever 6.