What is the recommended treatment for strep throat?

Treatment for Strep Throat

Penicillin V (250 mg four times daily or 500 mg twice daily) or amoxicillin (50 mg/kg once daily, maximum 1000 mg) for 10 days is the first-line treatment for strep throat, with penicillin preferred due to its narrow spectrum, proven efficacy, safety, and low cost. 1

First-Line Antibiotic Regimens for Non-Allergic Patients

• Penicillin V remains the drug of choice with dosing of 250 mg four times daily OR 500 mg twice daily for 10 days in adolescents and adults 1
• For children, penicillin V 250 mg two or three times daily for 10 days is recommended 1
• Amoxicillin 50 mg/kg once daily (maximum 1000 mg) for 10 days is equally effective and often preferred in children due to better palatability and once-daily dosing convenience 1, 2
• Amoxicillin can alternatively be dosed at 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1
• Intramuscular benzathine penicillin G as a single dose (600,000 units if <27 kg; 1,200,000 units if ≥27 kg) ensures compliance when adherence to oral therapy is uncertain 1, 2

The rationale for penicillin as first-line is compelling: no documented resistance of Group A streptococcus to penicillin has emerged despite decades of use, it has a narrow spectrum that minimizes disruption of normal flora, adverse reactions are rare, and cost is minimal. 1

Treatment Duration: Why 10 Days Matters

• The full 10-day course is essential for all antibiotics except azithromycin to achieve maximal pharyngeal eradication and prevent acute rheumatic fever 1, 2
• Shorter courses have not been adequately validated and increase the risk of treatment failure and rheumatic fever 1, 2
• Most oral antibiotics must be administered for the conventional 10-day course to achieve maximal pharyngeal eradication of Group A streptococci 1

While some research suggests 5-7 day courses may be non-inferior 3, the guideline consensus remains firm on 10 days for penicillin and amoxicillin because definitive comprehensive studies validating shorter courses are lacking, and these shorter regimens typically involve broader-spectrum, more expensive antibiotics. 1

Penicillin-Allergic Patients

For Non-Immediate (Non-Anaphylactic) Penicillin Allergy:

• First-generation cephalosporins are preferred alternatives 1, 2
• Cephalexin 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days 1, 2
• Cefadroxil 30 mg/kg once daily (maximum 1 g) for 10 days 1
• Avoid cephalosporins in patients with immediate hypersensitivity to penicillin (anaphylaxis, urticaria, angioedema) due to cross-reactivity risk 1

For Immediate-Type Hypersensitivity (Anaphylaxis):

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

Critical caveat: Resistance of Group A streptococcus to azithromycin and clarithromycin is well-known and varies geographically and temporally. 1, 4 There is significant resistance to these macrolides in some parts of the United States. 5 Susceptibility testing should be performed when patients are treated with azithromycin. 4

Adjunctive Symptomatic Treatment

• Acetaminophen or NSAIDs can be used for moderate to severe symptoms or high fever 1
• Aspirin should be avoided in children due to Reye's syndrome risk 1
• Adjunctive corticosteroids are not recommended 1

Treatment Failures and Recurrent Episodes

• If treatment fails despite adequate compliance, retreatment with the same regimen is acceptable if compliance was good 2
• For chronic carriers or multiple treatment failures, clindamycin 20-30 mg/kg per day in three doses (maximum 300 mg per dose) for 10 days is effective 1, 2
• Amoxicillin/clavulanate 40 mg amoxicillin per kg per day in three doses (maximum 2000 mg amoxicillin per day) for 10 days is another option for chronic carriers 1
• Patients with recurrent pharyngitis may be chronic carriers experiencing repeated viral infections rather than true recurrent streptococcal infections 1

Common Pitfalls to Avoid

• Do not use tetracyclines, sulfonamides, or trimethoprim-sulfamethoxazole as they fail to eradicate streptococci effectively 6
• Do not shorten the antibiotic course to less than 10 days (except for azithromycin 5 days), as this increases treatment failure risk 2, 6
• Do not perform routine follow-up throat cultures after completing therapy in asymptomatic patients 1, 7
• Do not test or treat asymptomatic household contacts routinely 1
• Avoid ampicillin and amoxicillin in patients with concurrent infectious mononucleosis due to high risk of rash; use cephalosporin or macrolide instead if strep treatment is needed 7

When to Consider Alternative Approaches

• Intramuscular benzathine penicillin G is preferred when compliance with oral therapy is questionable 1
• Patients become non-contagious after 24 hours of appropriate antibiotic therapy 7
• Patients with worsening symptoms after appropriate antibiotic initiation or with symptoms lasting 5 days after starting treatment should be reevaluated 5