What is the recommended treatment for strep throat?

Treatment of Strep Throat

Penicillin or amoxicillin for 10 days is the recommended first-line treatment for strep throat due to proven efficacy, narrow spectrum, safety, and low cost, with no documented penicillin resistance ever reported in Group A streptococcus. 1

First-Line Treatment for Non-Allergic Patients

• Penicillin V or amoxicillin remains the drug of choice for patients without penicillin allergy, with strong, high-quality evidence supporting this recommendation 1
• Amoxicillin is often preferred over penicillin V in young children due to better palatability and acceptance of the suspension formulation 1
• Once-daily amoxicillin at 50 mg/kg (maximum 1000 mg) for 10 days is effective and may enhance adherence compared to multiple daily dosing 1
• Twice-daily dosing of penicillin is as efficacious as more frequent dosing regimens, while once-daily penicillin shows decreased efficacy and should not be used 2
• A full 10-day course is mandatory to achieve maximal pharyngeal eradication and prevent acute rheumatic fever, even though symptoms typically resolve within 3-4 days 1, 3

Treatment for Penicillin-Allergic Patients

Non-Anaphylactic Penicillin Allergy

• First-generation cephalosporins (cephalexin or cefadroxil) are the preferred first-line alternatives for patients with non-immediate penicillin allergies 1, 3
• Cephalexin: 20 mg/kg per dose twice daily (maximum 500 mg/dose) for 10 days 3
• Cefadroxil: 30 mg/kg once daily (maximum 1 gram) for 10 days 3
• Cross-reactivity risk with penicillin is less than 3% for first-generation cephalosporins, making them safe in most penicillin-allergic patients 4

Immediate/Anaphylactic Penicillin Allergy

• Patients with immediate hypersensitivity reactions should avoid all beta-lactam antibiotics, including cephalosporins, due to up to 10% cross-reactivity risk 1, 3
• Clindamycin is the preferred alternative for anaphylactic penicillin allergy: 7 mg/kg per dose three times daily (maximum 300 mg/dose) for 10 days 1, 3
• Clindamycin resistance among Group A streptococcus isolates in the United States is approximately 1%, making it highly reliable 1, 3
• Clindamycin demonstrates high efficacy in eradicating streptococci, even in chronic carriers 3

Macrolide Alternatives

• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days is an acceptable alternative for immediate penicillin allergy 1, 3
• Clarithromycin: 7.5 mg/kg per dose twice daily (maximum 250 mg/dose) for 10 days 1, 3
• Erythromycin: 20-40 mg/kg/day divided 2-3 times daily for 10 days, though less preferred due to gastrointestinal side effects 3
• Critical caveat: Macrolide resistance among Group A streptococcus ranges from 5-8% in the United States and varies geographically, making clindamycin or first-generation cephalosporins preferred in areas with high macrolide resistance 3, 5

Special Considerations

Concurrent Infectious Mononucleosis

• Avoid ampicillin and amoxicillin in patients with concurrent streptococcal pharyngitis and infectious mononucleosis due to risk of severe rash 4
• Use first-generation cephalosporin or macrolide if antibiotic treatment is indicated for documented Group A streptococcal infection 4

Treatment Duration and Timing

• Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 3
• Patients become non-contagious after 24 hours of appropriate antibiotic therapy 4
• Treatment should continue for minimum 48-72 hours beyond symptom resolution or evidence of bacterial eradication 6

Post-Treatment Follow-Up

• Do not perform routine follow-up throat cultures or rapid antigen tests in asymptomatic patients who have completed therapy 4, 3
• Follow-up testing should only be considered in special circumstances, such as patients with history of rheumatic fever 3

Antibiotics to Avoid

• Tetracyclines should not be used due to high prevalence of resistant strains 1
• Sulfonamides and trimethoprim-sulfamethoxazole should not be used as they do not eradicate Group A streptococcus 1, 7
• Older fluoroquinolones (ciprofloxacin) have limited activity against Group A streptococcus and should not be used 1
• Newer fluoroquinolones (levofloxacin, moxifloxacin) are unnecessarily broad-spectrum and not recommended for routine treatment 1

Adjunctive Symptomatic Treatment

• Acetaminophen or NSAIDs (ibuprofen) should be considered for moderate to severe symptoms or high fever 3, 7
• Aspirin must be avoided in children due to risk of Reye syndrome 3
• Corticosteroids are not recommended as adjunctive therapy 3

Common Pitfalls to Avoid

• Do not shorten antibiotic courses to less than 10 days (except azithromycin's 5-day regimen), as this increases treatment failure rates and risk of complications 3
• Do not use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to 10% cross-reactivity risk 3
• Do not prescribe broad-spectrum cephalosporins when narrow-spectrum first-generation agents are appropriate, as they are more expensive and promote antibiotic resistance 1, 3
• Do not assume all penicillin-allergic patients cannot receive cephalosporins—only those with immediate/anaphylactic reactions should avoid them 3
• Be aware of local macrolide resistance patterns before prescribing azithromycin or clarithromycin 3, 5