Treatment of Strep Pharyngitis in Teenagers
Penicillin V is the first-line treatment for strep pharyngitis in teenagers, administered at a dose of 250 mg three times daily for 10 days. 1
First-Line Treatment Options
Penicillin V:
- Dosage: 250 mg three times daily for 10 days
- Gold standard treatment recommended by the Infectious Diseases Society of America, American College of Physicians, and American Academy of Pediatrics
- Remains the drug of choice due to:
- Narrow spectrum
- Proven efficacy
- Low cost
- Minimal side effects
Amoxicillin (alternative first-line):
- Dosage: 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days
- Better palatability than penicillin, making it suitable for teenagers who may have difficulty with medication adherence 1
Alternative Treatment Options (for penicillin-allergic patients)
Azithromycin:
Clindamycin:
- Dosage: 300-450 mg orally three times daily for 10 days 1
- Reserved for patients with true penicillin allergy
Diagnostic Considerations
- Diagnosis should be confirmed using the Centor Criteria and/or Rapid Antigen Detection Tests (RADTs) before initiating antibiotic therapy 1
- Clinical features alone are insufficient for diagnosis
- RADTs have 90-95% sensitivity for detecting Group A Streptococcus
Treatment Duration
While traditional treatment duration is 10 days, some recent evidence suggests shorter courses may be effective:
- A 2022 study found that 5-7 day antibiotic courses were not less effective than traditional 10-day courses for strep pharyngitis 4
- However, the current guidelines from major medical societies still recommend 10-day courses to prevent complications like rheumatic fever 1
Symptom Management
- Pain relief: Ibuprofen or acetaminophen for sore throat symptoms and fever control
- Hydration: Encourage adequate fluid intake
- Return to school: Patients can return to school after completing 24 hours of appropriate antibiotic therapy, provided they are feeling well and fever has resolved 1
Important Considerations
- Compliance: Poor adherence to the full 10-day regimen is a major cause of treatment failure
- Follow-up: Routine follow-up throat cultures are not indicated for asymptomatic patients who have completed appropriate therapy 1
- Prevention: Hand hygiene and avoiding close contact with infected individuals are important preventive measures
Treatment Failure
If symptoms persist or worsen after 48-72 hours of antibiotic therapy:
- Evaluate for treatment failure
- Consider whether the patient is experiencing true GAS infections or is a chronic carrier with viral infections
- Consider alternative antibiotics if appropriate
Remember that proper treatment of strep pharyngitis is crucial not only for symptom relief but also for preventing serious complications such as rheumatic fever and post-streptococcal glomerulonephritis.