From the Guidelines
For a patient recently treated with amoxicillin who develops strep pharyngitis, cephalexin should be prescribed as a first-line alternative antibiotic, given its lower rate of relapse, good tolerability, and narrow spectrum, as recommended by the most recent guidelines 1.
Key Considerations
- The patient's recent treatment with amoxicillin may indicate antibiotic resistance or the presence of beta-lactamase-producing organisms in the pharynx, making alternative antibiotics necessary.
- Cephalexin is a suitable alternative, with a recommended dose of 20 mg/kg/dose twice daily (max = 500 mg/dose) for 10 days, as per the guidelines 1.
- Other options like clindamycin, azithromycin, or clarithromycin may be considered based on patient-specific factors, such as medication allergies, local resistance patterns, and comorbidities that might affect drug metabolism.
Treatment Recommendations
- Cephalexin: 20 mg/kg/dose twice daily (max = 500 mg/dose) for 10 days.
- Clindamycin: 7 mg/kg/dose 3 times daily (max = 300 mg/dose) for 10 days, as an alternative option 1.
- Azithromycin: 12 mg/kg once daily (max = 500 mg) for 5 days, as an alternative option 1.
Importance of Completing the Full Course of Antibiotics
- It is crucial for the patient to complete the full course of antibiotics, even if symptoms improve quickly, to prevent complications like rheumatic fever or post-streptococcal glomerulonephritis, as emphasized by the guidelines 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 NOTE: Penicillin by the intramuscular route is the usual drug of choice in the treatment of Streptococcus pyogenes infection and the prophylaxis of rheumatic fever. Azithromycin is often effective in the eradication of susceptible strains of Streptococcus pyogenes from the nasopharynx Because some strains are resistant to azithromycin, susceptibility tests should be performed when patients are treated with azithromycin.
The patient should be prescribed azithromycin as an alternative to first-line therapy, as they have recently been treated with amoxicillin. However, penicillin is the usual drug of choice for treating Streptococcus pyogenes infection.
- Key considerations:
- Susceptibility tests should be performed to ensure the effectiveness of azithromycin.
- Azithromycin may not be effective in preventing rheumatic fever.
- The patient's recent treatment with amoxicillin should be taken into account when selecting an antibiotic. 2
From the Research
Antibiotic Treatment for Strep Pharyngitis
If a patient was recently treated with amoxicillin and develops strep pharyngitis, the following antibiotics can be prescribed:
- Penicillin and amoxicillin are first-line antibiotics, with a recommended course of 10 days 3
- First-generation cephalosporins are recommended for patients with nonanaphylactic allergies to penicillin 3, 4
- Azithromycin and clarithromycin can be used, but there is significant resistance to these antibiotics in some parts of the United States 3
- Erythromycin is an option in patients with penicillin allergy 4
Considerations for Antibiotic Treatment
When prescribing antibiotics for strep pharyngitis, the following should be considered:
- Clinical decision rules should be used to assess the risk of group A beta-hemolytic streptococcal infection, followed by rapid antigen testing if a diagnosis is unclear 3
- A throat culture is recommended in children and adolescents after a negative rapid antigen test result 3
- Patients with worsening symptoms after appropriate antibiotic initiation or with symptoms lasting 5 days after the start of treatment should be reevaluated 3
- The use of antibiotics with narrow spectrums of activity is appropriate for treating strep throat 5
Alternative Treatment Options
Alternative treatment options for strep pharyngitis include: