What is the treatment for bacterial pharyngitis with Augmentin (amoxicillin/clavulanate)?

Augmentin for Bacterial Pharyngitis: Reserve for Treatment Failures and Chronic Carriers

Augmentin (amoxicillin-clavulanate) is NOT first-line therapy for streptococcal pharyngitis—penicillin or amoxicillin alone remains the drug of choice due to proven efficacy, narrow spectrum, safety, and low cost. 1 Augmentin should be reserved for specific situations: treatment failures after penicillin therapy, chronic streptococcal carriers requiring eradication, or when compliance with oral penicillin is questionable. 1

When Augmentin Is Appropriate

Treatment Failures

• For patients with persistent symptoms and positive cultures after completing a course of penicillin or amoxicillin, Augmentin 40 mg amoxicillin/kg/day in 3 doses (maximum 2000 mg amoxicillin/day) for 10 days is a reasonable option. 1
• Augmentin has been shown to yield high rates of pharyngeal eradication of streptococci when penicillin treatment has failed. 1
• This scenario occurs more frequently with oral penicillin than intramuscular benzathine penicillin G. 1

Chronic Streptococcal Carriers

• Augmentin is effective for eradicating chronic carriage when treatment is indicated (though most carriers do not require therapy). 1
• Carrier eradication may be considered during community outbreaks of rheumatic fever or invasive GAS infection, or in families with excessive anxiety about GAS infections. 1

Why NOT First-Line?

• Penicillin has never developed resistance in Group A Streptococcus anywhere in the world, making it the most reliable choice. 1, 2
• Augmentin has a much broader spectrum than penicillin, unnecessarily increasing selection pressure for antibiotic-resistant flora. 1
• Augmentin is significantly more expensive than penicillin or amoxicillin alone. 1
• The clavulanate component adds no benefit for uncomplicated streptococcal pharyngitis, as GAS does not produce beta-lactamase. 1

Correct First-Line Treatment

For Non-Allergic Patients

• Penicillin V 500 mg orally twice daily for 10 days OR Amoxicillin 500 mg twice daily (or 1000 mg once daily) for 10 days. 1
• Intramuscular benzathine penicillin G (600,000 U for <27 kg; 1,200,000 U for ≥27 kg) as a single dose is equally effective and ensures compliance. 1

For Penicillin-Allergic Patients

• Non-immediate allergy: First-generation cephalosporins (cephalexin 500 mg twice daily for 10 days) are preferred. 1, 3
• Immediate/anaphylactic allergy: Clindamycin 300 mg three times daily for 10 days (only ~1% resistance in US) or azithromycin 500 mg once daily for 5 days (but 5-8% macrolide resistance). 1, 3

Critical Treatment Duration

• A full 10-day course is essential for all antibiotics except azithromycin to achieve maximal pharyngeal eradication and prevent acute rheumatic fever. 1, 3, 2
• Shortening the course by even a few days results in appreciable increases in treatment failure rates. 3

Common Pitfalls to Avoid

• Do not prescribe Augmentin as first-line therapy when penicillin or amoxicillin can be used—this unnecessarily broadens antibiotic spectrum and increases cost. 1
• Do not assume treatment failure without considering chronic carriage with intercurrent viral infection—carriers with viral pharyngitis will have positive cultures but don't need retreatment. 1, 4
• Do not routinely retest asymptomatic patients after treatment—post-treatment cultures are indicated only for those who remain symptomatic or have recurrent symptoms. 1, 4

Sample Prescription (When Appropriate)

Only prescribe Augmentin if:

• Patient failed initial penicillin/amoxicillin therapy AND remains symptomatic
• Patient is a documented chronic carrier requiring eradication for specific indications

Dosing:

• Adults: Augmentin 875 mg/125 mg orally twice daily for 10 days
• Pediatrics: 40 mg amoxicillin/kg/day divided three times daily (maximum 2000 mg amoxicillin/day) for 10 days 1

Otherwise, prescribe penicillin or amoxicillin as first-line therapy. 1, 5