What is the recommended antibiotic treatment for streptococcal (strep) pharyngitis?

From the Guidelines

Penicillin V 500 mg orally twice daily for 10 days is the recommended antibiotic treatment for strep throat, as it has been shown to be effective in eradicating the infecting organism and preventing complications such as rheumatic fever 1. The diagnosis of strep throat should be established using the Centor clinical scoring system or rapid antigen test, and antibiotics should only be used in patients with a high likelihood of streptococcal infection (3-4 Centor criteria) 1. For patients with penicillin allergy, alternatives such as cephalexin or azithromycin may be used, but the choice of antibiotic should be based on the severity of the allergy and the patient's medical history 1. It is essential to complete the full course of antibiotics, even if symptoms improve within a few days, to prevent complications and ensure that the infection is fully eradicated 1. Supportive care with acetaminophen or ibuprofen for pain and fever, along with adequate hydration and rest, is also recommended to help manage symptoms and improve quality of life 1. Some key points to consider when treating strep throat include:

• The importance of accurate diagnosis to prevent unnecessary antibiotic use and reduce the risk of antibiotic resistance 1
• The need to complete the full course of antibiotics to prevent complications and ensure that the infection is fully eradicated 1
• The use of supportive care measures such as pain management and hydration to help manage symptoms and improve quality of life 1
• The consideration of alternative antibiotics for patients with penicillin allergy, and the importance of choosing an antibiotic that is effective and safe for the patient 1.

From the FDA Drug Label

Pharyngitis/tonsillitis caused by Streptococcus pyogenes as an alternative to first-line therapy in individuals who cannot use first-line therapy Azithromycin is often effective in the eradication of susceptible strains of Streptococcus pyogenes from the nasopharynx In three double-blind controlled studies, conducted in the United States, azithromycin (12 mg/kg once a day for 5 days) was compared to penicillin V (250 mg three times a day for 10 days) in the treatment of pharyngitis due to documented Group A β-hemolytic streptococci (GABHS or S. pyogenes) Azithromycin was clinically and microbiologically statistically superior to penicillin at Day 14 and Day 30 with the following clinical success (i.e., cure and improvement) and bacteriologic efficacy rates (for the combined evaluable patient with documented GABHS)

Antibiotic treatment for strep throat: Azithromycin is effective in the treatment of pharyngitis/tonsillitis caused by Streptococcus pyogenes, with a clinical success rate of 98% at Day 14 and 94% at Day 30, as compared to penicillin V 2. However, penicillin is the usual drug of choice for the treatment of Streptococcus pyogenes infection and the prophylaxis of rheumatic fever. Azithromycin can be used as an alternative to first-line therapy in individuals who cannot use first-line therapy.

• Key points:
  • Azithromycin is effective against Streptococcus pyogenes
  • Clinical success rate: 98% at Day 14 and 94% at Day 30
  • Can be used as an alternative to first-line therapy in individuals who cannot use first-line therapy
  • Penicillin is the usual drug of choice for the treatment of Streptococcus pyogenes infection and the prophylaxis of rheumatic fever 2 2

From the Research

Antibiotic Treatment for Strep Throat

• The efficacy of different antibiotics in treating strep throat has been compared in several studies 3, 4, 5, 6, 7.
• Penicillin and amoxicillin are commonly recommended as first-line antibiotics for strep throat, with a recommended course of 10 days 4.
• Alternative antibiotics such as clarithromycin and cephalosporins have also been shown to be effective in treating strep throat 3, 5, 6.
• A study comparing clarithromycin and penicillin found that clarithromycin had a higher bacteriologic cure rate and was as well tolerated as penicillin 3.
• Another study comparing amoxicillin and penicillin V found that a 6-day course of amoxicillin was as effective as a 10-day course of penicillin V in treating strep throat 7.
• The choice of antibiotic may depend on factors such as patient age, allergy history, and local resistance patterns 4, 5.

Comparison of Antibiotics

• Cephalosporins versus penicillin: low-certainty evidence suggests that cephalosporins may have a lower clinical relapse rate compared to penicillin 5.
• Macrolides versus penicillin: low-certainty evidence suggests that there may be no difference in symptom resolution between macrolides and penicillin 5.
• Azithromycin versus amoxicillin: very low-certainty evidence suggests that azithromycin may have a higher rate of adverse events compared to amoxicillin 5.
• Carbacephem versus penicillin: low-certainty evidence suggests that carbacephem may have a higher symptom resolution rate compared to penicillin 5.

Adverse Events and Safety

• Adverse events related to antibiotic treatment were reported in several studies, with the most common events being gastrointestinal symptoms and allergic reactions 3, 6, 7.
• The safety profile of different antibiotics may vary, with some antibiotics having a higher risk of adverse events compared to others 5, 7.