What is the recommended treatment for a patient with streptococcal pharyngitis (strep throat) and sore throat?

Management of Streptococcal Pharyngitis

First-Line Antibiotic Treatment

Penicillin V or amoxicillin for 10 days is the recommended treatment for confirmed streptococcal pharyngitis, with penicillin remaining the drug of choice due to its proven efficacy, narrow spectrum, safety profile, and low cost. 1, 2

Penicillin V Dosing

• Children: 250 mg twice or three times daily for 10 days 1, 2
• Adolescents and adults: 250 mg three to four times daily OR 500 mg twice daily for 10 days 1, 2
• Twice-daily dosing is as effective as more frequent regimens and may improve adherence 3, 4

Amoxicillin as Alternative

• Preferred for young children due to better palatability of suspension 1, 2
• Dosing: 50 mg/kg once daily (maximum 1000 mg) for 10 days 1, 2
• Once-daily amoxicillin is equally effective to multiple-daily-dose penicillin V and may enhance adherence 1, 5

Intramuscular Option

• Benzathine penicillin G when oral adherence is a concern 1, 2
• Dosing: 600,000 units for patients <27 kg; 1.2 million units for patients ≥27 kg, single dose 1, 2

Treatment for Penicillin-Allergic Patients

Non-Anaphylactic Allergy

• First-generation cephalosporins (e.g., cephalexin) for 10 days 1, 2, 6
• Cephalexin: 20 mg/kg/dose twice daily (maximum 500 mg/dose) 6

Anaphylactic Allergy

• Clindamycin: 7 mg/kg/dose three times daily (maximum 300 mg/dose) for 10 days 1, 6
• Clarithromycin: 7.5 mg/kg/dose twice daily (maximum 250 mg/dose) for 10 days 1, 6
• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 2, 6

Important caveat: Macrolide resistance varies geographically and is increasing in some U.S. regions, making these less reliable alternatives 6, 7, 8

Critical Treatment Duration

The 10-day duration for penicillin, amoxicillin, and most antibiotics is essential to maximize bacterial eradication and prevent acute rheumatic fever. 1, 2

• Azithromycin is the only exception with an approved 5-day course 2
• Shorter courses of penicillin (less than 10 days) are less effective and should not be used 2, 3
• The 10-day standard remains necessary despite evidence that some newer antibiotics may be effective in shorter courses, as guidelines prioritize rheumatic fever prevention 2

Diagnostic Confirmation Before Treatment

Antibiotics should only be prescribed after confirming streptococcal infection with rapid antigen detection test (RADT) or throat culture. 1, 2

• A positive RADT is diagnostic and requires no backup culture 1, 2
• A negative RADT in children and adolescents should be followed by throat culture 1, 2
• Clinical features alone cannot reliably distinguish bacterial from viral pharyngitis 1, 2, 9

Clinical Decision Tools

• Use Centor criteria to identify patients needing testing 1, 9, 8
• Patients with 3-4 Centor criteria have higher likelihood of streptococcal infection and warrant RADT 1
• Patients with 0-2 Centor criteria should not receive antibiotics 1

Symptomatic Management

Pain and Fever Control

• Ibuprofen or acetaminophen for moderate to severe symptoms or high fever 1, 2, 6
• NSAIDs are more effective than acetaminophen for pain and fever relief 9
• Avoid aspirin in children due to Reye syndrome risk 2, 6

Not Recommended

• Corticosteroids provide minimal benefit and are not recommended for routine use 6, 9, 8
• Zinc gluconate is not recommended 1

Common Pitfalls to Avoid

• Do not treat without diagnostic confirmation: 60% of adults with sore throat receive antibiotics, but only 10% have streptococcal infection 8
• Do not use broad-spectrum antibiotics when narrow-spectrum options are effective 2
• Do not prescribe shorter courses of penicillin or amoxicillin (less than 10 days) 2
• Do not perform routine post-treatment cultures in asymptomatic patients who completed therapy 1, 2
• Do not test or treat asymptomatic household contacts routinely 1

Follow-Up Considerations

• Patients should be reevaluated if symptoms worsen after starting antibiotics or persist 5 days after treatment initiation 8
• For recurrent episodes, determine whether these represent true recurrent infections versus chronic carriage with viral infections 2, 6
• Post-treatment throat cultures are not routinely recommended but may be considered in special circumstances 1