From the Guidelines
Strep pharyngitis is best treated with antibiotics, specifically penicillin as the first-line therapy, as recommended by the Infectious Diseases Society of America in their 2012 guideline update 1.
Treatment Regimens
For adults, the recommended regimen is penicillin V 500 mg orally twice daily for 10 days, or a single intramuscular injection of benzathine penicillin G 1.2 million units if oral compliance is a concern.
- For penicillin-allergic patients, alternatives include cephalexin 500 mg twice daily for 10 days (if no anaphylactic reaction history), or azithromycin 500 mg once daily for 5 days, as supported by the evidence from 1.
- Children require weight-based dosing: penicillin V 250 mg twice daily for ages 5-11 and 500 mg twice daily for ages 12+ for 10 days.
Importance of Prompt Treatment
Treatment should begin promptly after diagnosis to reduce symptom duration, prevent complications like rheumatic fever and peritonsillar abscess, and decrease transmission, as emphasized in the guidelines 1.
- Patients typically become non-contagious after 24 hours of antibiotic therapy.
Supportive Care
Supportive care with acetaminophen or ibuprofen for pain and fever, along with adequate hydration and rest, is also important.
- Completing the full antibiotic course is essential even if symptoms improve quickly to ensure complete eradication of the bacteria, a principle supported by multiple studies including 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 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, at 95% at Day 14 and 77% at Day 30, compared to 73% and 63% for penicillin V. 2
From the Research
Treatment Options for Strep Pharyngitis
- Penicillin V is a commonly recommended first-line therapy for streptococcal pharyngitis, typically given for 10 days 3, 4.
- Alternative treatments include other penicillins, macrolides, and cephalosporins, with cephalosporins potentially offering higher bacteriologic eradication rates than penicillin V 3.
- Azithromycin has been studied as a potential treatment, but its efficacy in eliminating GABHS from the throat is inferior to penicillin V 5, 6.
- Amoxicillin given once daily has been shown to be as effective as penicillin V given three times a day in treating GABHS pharyngitis 7.
Considerations for Treatment
- The choice of antibiotic should take into account factors such as patient compliance, palatability, and potential allergies 3, 4.
- Resistance to certain antibiotics, such as azithromycin and clarithromycin, is a concern in some regions 4.
- Clinical decision rules and rapid antigen testing can help determine the likelihood of group A beta-hemolytic streptococcal infection and guide antibiotic treatment 4.
Bacteriologic Eradication and Clinical Efficacy
- Studies have shown that while azithromycin may be clinically effective in treating strep pharyngitis, its ability to eradicate GABHS from the throat is lower than that of penicillin V 5, 6.
- Amoxicillin given once daily has been shown to be as effective as penicillin V in eradicating GABHS and achieving clinical success 7.
- The relationship between bacteriologic eradication and clinical outcome is not always clear, with some studies finding no correlation between the two 5, 6.