Augmentin (Amoxicillin-Clavulanate) Dosing for Group A Streptococcal Infections
Amoxicillin-clavulanate (Augmentin) is not recommended as first-line therapy for Group A streptococcal pharyngitis but can be used in specific situations with a standard dosing of 40 mg amoxicillin/kg/day divided into three doses (maximum 2,000 mg amoxicillin per day) for 10 days. 1
First-Line Treatment Options
- Penicillin V remains the treatment of choice for Group A streptococcal pharyngitis due to its proven efficacy, safety, narrow spectrum, and low cost 2
- Amoxicillin alone is an acceptable alternative to penicillin V, especially in young children, primarily due to better taste acceptance of the suspension 2, 1
- The standard dosing for amoxicillin is 50 mg/kg once daily (maximum 1,000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1
When to Use Augmentin (Amoxicillin-Clavulanate)
Augmentin is not first-line therapy but may be indicated in:
- Treatment failures with first-line agents 1
- Chronic carriers of Group A Streptococcus 1
- Mixed infections where beta-lactamase producing organisms may be present 3, 4
- Recurrent streptococcal tonsillitis 4
Augmentin Dosing for Group A Streptococcal Infections
- Standard dosing: 40 mg amoxicillin/kg/day divided into three doses (maximum 2,000 mg amoxicillin per day) for 10 days 1
- For adults: The typical adult dosage is 500 mg (amoxicillin component) three times daily for 10 days 2
- The maximum daily dose of the amoxicillin component should not exceed 2,000 mg per day, even in morbidly obese children 1
Treatment Duration
- A full 10-day course is recommended for Augmentin treatment of Group A streptococcal pharyngitis 2, 1
- Shorter courses (5 days) have been studied but are not currently endorsed by guidelines due to insufficient comprehensive evidence 2, 5
Alternative Options for Penicillin-Allergic Patients
For patients with penicillin allergy, alternative options include:
- Cephalexin: 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 10 days (avoid in immediate hypersensitivity to penicillin) 2
- Clindamycin: 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days 2
- Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 2
- Clarithromycin: 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days 2
Clinical Considerations and Pitfalls
- Augmentin has a broader spectrum of activity than needed for most cases of Group A streptococcal pharyngitis, which can lead to unnecessary disruption of normal flora 2, 6
- Be aware of local resistance patterns when selecting antimicrobial therapy 1
- Compliance may be an issue with three-times-daily dosing of Augmentin compared to once-daily amoxicillin 7
- Cost is higher for Augmentin compared to penicillin V or amoxicillin alone 2, 6
- Monitor for gastrointestinal side effects, which are more common with Augmentin than with penicillin or amoxicillin alone 6
Efficacy in Mixed Infections
- Augmentin has demonstrated superior efficacy in mixed infections where beta-lactamase producing organisms are present 3, 4
- In recurrent tonsillitis, Augmentin has shown better eradication rates and lower recurrence compared to penicillin V, likely due to its activity against beta-lactamase producing bacteria in tonsillar tissue 4