What is the treatment for Streptococcal (Strep) pharyngitis?

From the Guidelines

Strep pharyngitis is best treated with a 10-day course of oral penicillin V (250-500 mg twice daily for adults, or 250 mg 2-3 times daily for children), or a single intramuscular injection of benzathine penicillin G (1.2 million units for adults, 600,000 units for children <60 lbs). For penicillin-allergic patients, alternatives include azithromycin (12 mg/kg once daily, max 500 mg, for 5 days) or clindamycin (7 mg/kg/dose 3 times daily, max 300 mg/dose, for 10 days) 1. Complete the full antibiotic course even if symptoms improve quickly to prevent complications like rheumatic fever. Symptomatic relief can be achieved with acetaminophen or ibuprofen for pain and fever, warm salt water gargles, and adequate hydration. Treatment is important because strep throat, caused by Group A Streptococcus bacteria, can lead to serious complications if untreated, including rheumatic heart disease and post-streptococcal glomerulonephritis. Patients should rest, stay home for 24 hours after starting antibiotics to prevent transmission, and can expect symptom improvement within 2-3 days of starting treatment.

Key Considerations

• The Infectious Diseases Society of America recommends penicillin V or benzathine penicillin G as the first-line treatment for strep pharyngitis 1.
• For patients with penicillin allergy, azithromycin or clindamycin are suitable alternatives 1.
• The full antibiotic course should be completed to prevent complications like rheumatic fever.
• Symptomatic relief can be achieved with over-the-counter pain medications and hydration.

Treatment Options

• Penicillin V: 250-500 mg twice daily for adults, or 250 mg 2-3 times daily for children
• Benzathine penicillin G: 1.2 million units for adults, 600,000 units for children <60 lbs
• Azithromycin: 12 mg/kg once daily, max 500 mg, for 5 days
• Clindamycin: 7 mg/kg/dose 3 times daily, max 300 mg/dose, for 10 days

Important Notes

• Treatment should be guided by the results of a throat culture or rapid antigen detection test (RADT) 1.
• Patients should be educated on the importance of completing the full antibiotic course and the potential complications of untreated strep pharyngitis.

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 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 Three U. S. Streptococcal Pharyngitis Studies Azithromycin vs. Penicillin V EFFICACY RESULTS Day 14 Day 30 Bacteriologic Eradication: Azithromycin 323/340 (95%) 255/330 (77%) Penicillin V 242/332 (73%) 206/325 (63%) Clinical Success (Cure plus improvement): Azithromycin 336/343 (98%) 310/330 (94%) Penicillin V 284/338 (84%) 241/325 (74%)

Azithromycin is effective in the treatment of strep pharyngitis. The clinical success rate for azithromycin was 98% at Day 14 and 94% at Day 30, compared to 84% and 74% for penicillin V, respectively. Bacteriologic eradication rates were also higher for azithromycin, with 95% at Day 14 and 77% at Day 30, compared to 73% and 63% for penicillin V. 2

From the Research

Strep Pharyngitis Treatment Options

• The treatment of streptococcal pharyngitis typically involves the use of antibiotics to prevent complications such as acute rheumatic fever and to hasten resolution of symptoms 3.
• Penicillin V is often recommended as the first-line treatment for streptococcal pharyngitis, given its efficacy and safety profile 3, 4.
• Alternative treatments, such as azithromycin, have been studied and shown to be effective in some cases, but may have lower bacteriologic eradication rates compared to penicillin V 5, 6.
• Cephalosporins are another option for treating streptococcal pharyngitis, and may offer higher bacteriologic eradication rates than penicillin V, although they can be more expensive and have a higher risk of adverse effects 3, 4.

Comparison of Azithromycin and Penicillin V

• Studies have compared the efficacy of azithromycin and penicillin V in treating streptococcal pharyngitis, with mixed results 5, 6, 7.
• Azithromycin has been shown to have similar clinical efficacy to penicillin V, but lower bacteriologic eradication rates 5, 6.
• Penicillin V has been shown to have higher bacteriologic eradication rates, but may require a longer treatment duration and more frequent dosing 5, 6.

Considerations for Treatment

• The choice of treatment for streptococcal pharyngitis should take into account factors such as the patient's age, medical history, and potential allergies or sensitivities to antibiotics 3, 4.
• The palatability of the antibiotic is also an important consideration, particularly in pediatric patients 3.
• The potential for resistance to antibiotics, such as macrolides, should also be considered when selecting a treatment option 3, 4.