What is the recommended treatment for Group A Streptococcal (GAS) infections?

From the Guidelines

The recommended treatment for Group A Streptococcal (GAS) infections is penicillin, which remains the first-line antibiotic therapy due to the lack of resistance development. For non-severe infections, oral penicillin V (phenoxymethylpenicillin) is typically prescribed at 250-500 mg two to four times daily for 10 days 1. For severe infections or patients unable to take oral medications, intravenous penicillin G is recommended. In penicillin-allergic patients, alternatives include first-generation cephalosporins (if no history of anaphylaxis), macrolides like azithromycin (500 mg on day 1, then 250 mg daily for 4 days), or clindamycin (300 mg three times daily for 10 days) 1.

Key Considerations

• The choice of antibiotic should be based on the patient's allergy history and the severity of the infection.
• Complete treatment courses are essential to prevent complications like rheumatic fever and post-streptococcal glomerulonephritis.
• Penicillin works by inhibiting bacterial cell wall synthesis, while clindamycin suppresses toxin production, making it valuable for toxin-mediated severe infections.

Treatment Options

• Penicillin V: 250-500 mg two to four times daily for 10 days
• Amoxicillin: 50 mg/kg once daily (max = 1000 mg) for 10 days
• Benzathine penicillin G: 1.2 million U intramuscularly for 1 dose
• Azithromycin: 12 mg/kg once daily (max = 500 mg) for 5 days
• Clindamycin: 7 mg/kg/dose three times daily (max = 300 mg/dose) for 10 days

Special Considerations

• Invasive GAS infections such as necrotizing fasciitis or streptococcal toxic shock syndrome require aggressive treatment with high-dose penicillin plus clindamycin, often with surgical debridement when appropriate.
• Patients with a history of anaphylaxis to penicillin should be treated with caution and alternative antibiotics should be considered.

From the FDA Drug Label

Antibiotic therapy for Group A β-hemolytic streptococcal infections should be maintained for at least 10 days to reduce the risk of rheumatic fever.

• The recommended treatment for Group A Streptococcal (GAS) infections is penicillin.
• The duration of therapy should be at least 10 days to reduce the risk of rheumatic fever 2.
• For most acute infections, treatment should be continued for at least 48 to 72 hours after the patient becomes asymptomatic 2.
• Penicillin V can be used to treat streptococcal infections, and therapy must be sufficient to eliminate the organism (10-day minimum) 3.
• Clindamycin can also be used to treat serious infections due to anaerobic bacteria, including β-hemolytic streptococcal infections, and treatment should continue for at least 10 days 4.

From the Research

Treatment Options for Group A Streptococcal (GAS) Infections

• The recommended treatment for GAS infections, particularly for GAS pharyngitis, typically involves the use of antibiotics 5, 6.
• Penicillin is often considered the first-line treatment due to its efficacy, safety, and narrow spectrum 6.
• Amoxicillin is also a commonly recommended antibiotic for treating GAS pharyngitis, especially in children 5.
• Other antibiotics such as cephalosporins, macrolides, and carbacephem may be considered as alternatives, but the evidence on their comparative efficacy is limited and often of low certainty 7, 8, 9.

Comparative Efficacy of Antibiotics

• Studies comparing different antibiotics for the treatment of GAS pharyngitis have found no significant differences in symptom resolution between cephalosporins and penicillin 7, 8, 9.
• Macrolides and penicillin have also shown similar efficacy in resolving symptoms, although macrolides may be associated with more adverse events in children 7, 8, 9.
• Carbacephem may provide better symptom resolution post-treatment compared to penicillin, particularly in children, but the evidence is of low certainty 7, 8, 9.

Considerations for Treatment

• The choice of antibiotic should be guided by factors such as the patient's age, allergy history, and the presence of any underlying medical conditions 5, 6.
• The use of antibiotics should be judicious and based on a confirmed diagnosis of GAS infection to minimize the risk of antimicrobial resistance 5, 6.
• In the context of antimicrobial stewardship, penicillin can be used as a first-line treatment if antibiotic therapy is indicated 9.