What is the recommended treatment for strep throat?

Treatment of Strep Throat

Penicillin or amoxicillin for 10 days is the first-line treatment for strep throat, with penicillin remaining the drug of choice due to its proven efficacy, safety, narrow spectrum, and low cost. 1, 2, 3

First-Line Treatment Options

For Patients Without Penicillin Allergy

Oral Penicillin V:

• Children: 250 mg twice or three times daily for 10 days 1, 3
• Adolescents and adults: 250 mg four times daily OR 500 mg twice daily for 10 days 1, 3
• Strong, high-quality evidence supports this regimen 1

Oral Amoxicillin (equally effective alternative with better adherence):

• Preferred dosing: 50 mg/kg once daily (maximum 1,000 mg) for 10 days 1, 2, 3, 4
• Alternative: 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1, 4
• Once-daily amoxicillin is as effective as penicillin V given three times daily, with improved compliance 5, 6, 7
• Amoxicillin at 40 mg/kg/day shows significantly better clinical cure (87.9% vs 70.9%) and bacteriologic cure (79.3% vs 54.5%) compared to lower-dose penicillin V 5
• Strong, high-quality evidence supports this regimen 1

Intramuscular Benzathine Penicillin G (for patients unlikely to complete oral therapy):

• < 60 lbs (27 kg): 600,000 units as a single dose 1, 2, 3
• ≥ 60 lbs: 1,200,000 units as a single dose 1, 2, 3
• Strong, high-quality evidence supports this regimen 1

Treatment for Penicillin-Allergic Patients

Non-Anaphylactic/Non-Immediate Penicillin Allergy

First-generation cephalosporins are the preferred alternative:

• Cephalexin: 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days 1, 8, 2
• Cefadroxil: 30 mg/kg once daily (maximum 1 g) for 10 days 1, 8
• Strong, high-quality evidence supports these regimens 1, 8
• Critical caveat: Avoid in patients with immediate/anaphylactic hypersensitivity to penicillin due to 10% cross-reactivity risk 1, 8

Immediate/Anaphylactic Penicillin Allergy

Clindamycin (preferred for severe allergy):

• Dosing: 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days 1, 8, 2, 3
• Strong, moderate-quality evidence 1, 8
• Highly effective in eradicating streptococci, even in chronic carriers 8, 2
• Resistance rate in the United States is approximately 1% 8

Macrolides (use with caution due to resistance):

• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 8, 2, 9
• Clarithromycin: 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days 1, 8
• Erythromycin estolate: 20-40 mg/kg/day divided 2-3 times daily for 10 days 1
• Strong, moderate-quality evidence 1, 8
• Important limitation: Macrolide resistance among Group A Streptococcus is approximately 5-8% in the United States, with significant geographic variation 8, 2, 10

Duration of Therapy

• Most antibiotics require a full 10-day course to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever 1, 8, 2, 3, 4
• Exception: Azithromycin requires only 5 days due to its prolonged tissue half-life 1, 8, 2, 9
• Twice-daily penicillin dosing is as efficacious as more frequent dosing 6
• Once-daily penicillin shows decreased efficacy (12 percentage points lower cure rate) and should not be used 6

Adjunctive Therapy

• Acetaminophen or NSAIDs can be used for moderate to severe symptoms or high fever 1, 8, 2, 3
• Avoid aspirin in children due to risk of Reye syndrome 1, 8, 2, 3
• Corticosteroids are not recommended as adjunctive therapy 1, 8, 2

Diagnostic Considerations Before Treatment

• Use clinical decision rules (Centor criteria) to assess risk: sudden onset sore throat, fever, tonsillar exudates, tender anterior cervical lymphadenopathy, absence of cough 1, 3, 10
• Patients with 3-4 Centor criteria should undergo rapid antigen detection test (RADT) or throat culture 1, 3
• Negative RADT in children and adolescents should be confirmed with throat culture 1, 3, 10
• Do not test or treat if clinical features strongly suggest viral etiology (cough, rhinorrhea, hoarseness, oral ulcers) 1, 3

Follow-Up and Special Situations

• Routine post-treatment testing is not recommended for asymptomatic patients who completed therapy 1, 2, 3
• Patients are non-contagious after 24 hours of appropriate antibiotic therapy 2
• Recurrent pharyngitis: Consider clindamycin, amoxicillin-clavulanate, or benzathine penicillin G with rifampin for chronic carriers 2, 3
• Household contacts: Do not routinely test or treat asymptomatic contacts unless special circumstances exist (outbreak, history of rheumatic fever) 1

Common Pitfalls to Avoid

• Do not prescribe antibiotics for likely viral pharyngitis (patients with cough, rhinorrhea, hoarseness) 1, 3
• Do not use once-daily penicillin due to decreased efficacy 6
• Do not use first-generation cephalosporins in patients with immediate/anaphylactic penicillin allergy 1, 8
• Do not use trimethoprim-sulfamethoxazole for strep throat due to high resistance rates 8
• Do not prescribe courses shorter than 10 days (except azithromycin at 5 days) as this leads to treatment failure 1, 8
• Be aware of local macrolide resistance patterns when prescribing azithromycin or clarithromycin 8, 10