From the Guidelines
Streptococcus pyogenes is susceptible to Augmentin (amoxicillin-clavulanate), and it is an effective treatment option for S. pyogenes infections, including pharyngitis (strep throat) and skin and soft tissue infections. The Infectious Diseases Society of America recommends amoxicillin-clavulanic acid as a treatment option for chronic carriers of Group A Streptococci, with a dosage of 40 mg amoxicillin/kg/d in 3 doses (max = 2000 mg amoxicillin/d) for 10 days 1. This recommendation is based on the effectiveness of amoxicillin-clavulanate in eliminating chronic streptococcal carriage.
Key Points to Consider
- The typical adult dosage of Augmentin for S. pyogenes infections is 875 mg amoxicillin/125 mg clavulanate twice daily or 500 mg amoxicillin/125 mg clavulanate three times daily for 7-10 days, depending on the infection site and severity.
- For children, the dosage is based on weight, typically 45 mg/kg/day divided into two doses.
- Augmentin works by combining amoxicillin, which disrupts bacterial cell wall synthesis, with clavulanate, which inhibits beta-lactamase enzymes that could otherwise inactivate amoxicillin.
- While S. pyogenes remains universally susceptible to penicillin and has not developed beta-lactamase production, Augmentin is sometimes preferred when mixed infections are suspected or in cases where broader coverage is desired.
- Patients should complete the full course of antibiotics even if symptoms improve before completion to ensure complete eradication of the bacteria.
Additional Considerations
- The Infectious Diseases Society of America also recommends oral therapy for ecthyma or impetigo with an agent active against S. aureus, unless cultures yield streptococci alone, in which case oral penicillin is the recommended agent 1.
- Systemic antimicrobials, such as Augmentin, should be used for infections during outbreaks of poststreptococcal glomerulonephritis to help eliminate nephritogenic strains of S. pyogenes from the community 1.
From the Research
Susceptibility of Streptococcus pyogenes to Augmentin
- Streptococcus pyogenes is generally susceptible to amoxicillin-clavulanate (Augmentin) 2, 3, 4, 5
- Studies have shown that amoxicillin-clavulanate is effective in eliminating S. pyogenes from wound infections, even in the presence of beta-lactamase-producing organisms such as Staphylococcus aureus 2
- In vitro studies have demonstrated that amoxicillin-clavulanate has a low propensity to select resistance mutations in S. pyogenes 3
- Clinical trials have shown that amoxicillin-clavulanate is effective in treating group A streptococcal tonsillopharyngitis, with eradication rates comparable to those of penicillin V 4
- The use of amoxicillin-clavulanate in the treatment of community-acquired respiratory tract infections is supported by its broad-spectrum antibacterial activity, coverage of beta-lactamase-producing pathogens, and favorable pharmacokinetic/pharmacodynamic profile 5
Resistance Patterns
- Macrolide resistance in S. pyogenes is a concern, with some studies reporting high rates of resistance 6, 4
- However, amoxicillin-clavulanate remains effective against S. pyogenes, even in areas with high rates of macrolide resistance 2, 3, 4, 5
- The emergence of S. pneumoniae strains with elevated penicillin MICs has been observed in certain geographical areas, but amoxicillin-clavulanate remains effective against these strains 5