What is the recommended management for strep throat?

Management of Streptococcal Pharyngitis

First-Line Antibiotic Treatment

Penicillin V (250 mg three to four times daily or 500 mg twice daily) or amoxicillin (50 mg/kg once daily, maximum 1000 mg) for a full 10 days is the definitive treatment for confirmed Group A streptococcal pharyngitis. 1

Diagnosis Before Treatment

• Confirm Group A streptococcal pharyngitis with either throat culture or rapid antigen detection test (RADT) before initiating antibiotics 2, 1
• A negative RADT in children and adolescents should be confirmed by throat culture due to lower sensitivity of rapid tests 2
• In adults, RADT alone is acceptable without culture confirmation of negative results due to lower disease incidence and minimal rheumatic fever risk 2

Antibiotic Selection and Dosing

Penicillin V remains the drug of choice due to its proven efficacy, safety, narrow spectrum, and low cost 2, 1

Adult dosing:

• Penicillin V: 250 mg three to four times daily OR 500 mg twice daily for 10 days 1

Pediatric dosing:

• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) for 10 days 1, 3
• Amoxicillin is preferred over penicillin V in young children primarily due to better palatability of the suspension 2

Critical Treatment Duration

The full 10-day course is essential to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever 2, 1, 3

• Patients become non-contagious after 24 hours of appropriate antibiotic therapy 4, 5
• Treatment should continue for at least 10 days for any infection caused by Streptococcus pyogenes to prevent acute rheumatic fever 3

Penicillin Allergy Alternatives

Non-Immediate (Delayed) Penicillin Allergy

First-generation cephalosporins (cephalexin or cefadroxil) for 10 days are the preferred alternatives 2, 1, 4

• Cross-reactivity risk is approximately 0.1% in patients with non-severe, delayed penicillin reactions 1
• Cross-reactivity risk is less than 3% overall, making cephalosporins safe in most penicillin-allergic patients 4

Immediate/Anaphylactic Penicillin Allergy

Use clindamycin, azithromycin, or clarithromycin 1

• Clindamycin is particularly effective with only 1% resistance rates in the United States 6, 4
• Erythromycin is a suitable alternative for penicillin-allergic patients 2, 4
• Do NOT use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to up to 10% cross-reactivity risk 1

Management of Treatment Failure

If symptoms persist after completing the full 10-day course:

Obtain a throat culture or RADT immediately to determine if Group A Streptococcus persists 6

If Culture Remains Positive (Treatment Failure)

Switch to clindamycin 300 mg three times daily for 10 days (preferred for adults) 6

• Alternative: Amoxicillin-clavulanate 875 mg twice daily for 10 days addresses beta-lactamase-producing co-pathogens 6
• Do NOT simply repeat penicillin V, as this has a high failure rate and delays appropriate treatment 6
• Penicillin failure rates have increased to approximately 30% in some studies 6

If Culture is Negative

• The persistent sore throat is likely viral or due to another non-streptococcal cause 6
• Discontinue antibiotics 6

Symptomatic Management

• Provide symptomatic relief with ibuprofen or acetaminophen for moderate to severe throat pain or fever 6
• Avoid aspirin in children due to Reye syndrome risk 6
• Corticosteroids are NOT recommended as adjunctive therapy 1, 6

Follow-Up and Testing

Do NOT perform routine follow-up throat cultures in asymptomatic patients who have completed therapy 2, 4

Exceptions requiring follow-up testing:

• Patients with history of rheumatic fever 6
• Recurrent symptomatic pharyngitis 6
• Symptoms that worsen after 72 hours of appropriate antibiotic therapy 1
• New symptoms suggesting complications (peritonsillar abscess, cervical lymphadenitis) 1

Management of Household Contacts

Do NOT routinely test or treat asymptomatic household contacts 2

• Approximately 25% of household contacts harbor Group A streptococci asymptomatically 2
• Testing and treatment of contacts is only indicated in rare situations with increased risk of frequent infections or nonsuppurative sequelae 2

Critical Pitfalls to Avoid

• Never use courses shorter than 10 days (except azithromycin's FDA-approved 5-day regimen), as shorter courses increase treatment failure and rheumatic fever risk 1
• Do NOT use macrolides as first-line alternatives for treatment failure unless documented immediate penicillin allergy exists, due to resistance rates of 5-8% in the United States 6
• Avoid ampicillin and amoxicillin in patients with concurrent infectious mononucleosis, as they cause a characteristic rash in this setting 4
• Do NOT prescribe antibiotics for symptom relief alone in patients with 0-2 Centor criteria 1