What is the recommended treatment for strep throat?

Treatment of Strep Throat

Penicillin V is the first-line treatment for strep throat (Group A Streptococcal pharyngitis), with a recommended dose of 250 mg three times a day for 10 days for adults, and for children: 600,000 U for <27 kg and 1,200,000 U for ≥27 kg. 1

Diagnosis and Assessment

• Use the Centor Criteria to assess the likelihood of Group A Streptococcal (GAS) pharyngitis 1:

  • Fever >38°C
  • Absence of cough
  • Tender anterior cervical lymphadenopathy
  • Tonsillar exudate
  • Age (higher score for younger patients)

• Rapid Antigen Detection Tests (RADTs) should be considered only in patients with high likelihood of streptococcal infections (3-4 Centor criteria) 1

Treatment Algorithm

First-line Treatment

• Penicillin V: 250 mg three times daily for 10 days (adults) 1
  • Children: 600,000 U for <27 kg and 1,200,000 U for ≥27 kg for 10 days 1
  • Treatment must continue for a full 10 days to prevent acute rheumatic fever 1, 2

Alternative Regimens

1. Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1, 2

   • Amoxicillin has shown better clinical and bacteriological cure rates compared to penicillin in some studies 3

2. For Penicillin-Allergic Patients:

   • Azithromycin: 12 mg/kg once daily (max 500 mg) for 5 days 1
   • Clindamycin: 300-450 mg orally three times daily for 10 days 1

Severe Infections (Hospitalized Patients)

• Clindamycin: 10-13 mg/kg/dose IV every 6-8 hours 1
• Vancomycin: 40-60 mg/kg/day divided every 6-8 hours IV (first choice for severe infections) 1

Symptomatic Relief

• Ibuprofen: 400mg every 6-8 hours (maximum 1200mg/day) for adults; 5-10mg/kg every 6-8 hours for children 1
• Acetaminophen: 500-1000mg every 4-6 hours (maximum 4000mg/day) for adults; 10-15mg/kg every 4-6 hours for children 1
• Maintain hydration: Drink plenty of fluids 1

Important Clinical Considerations

Duration of Treatment

• Treatment should continue for a minimum of 10 days to prevent acute rheumatic fever 1, 2
• Patients are considered non-contagious after 24 hours of effective antibiotic therapy 1

Treatment Failures

• If symptoms worsen or don't improve after 48-72 hours of antibiotic therapy, evaluate for treatment failure 1
• Consider compliance issues, reexposure to infected individuals, or bacterial resistance 4
• For recurrent streptococcal infections, a 5-day decolonization regimen with intranasal mupirocin and daily chlorhexidine washes may be considered 1

Special Populations

• Children under 3 years: Testing for GAS pharyngitis is usually not indicated; focus on age-appropriate symptomatic relief 1
• Children: Avoid aspirin due to risk of Reye syndrome 1
• Renal impairment: Patients with GFR <30 mL/min should NOT receive high-dose amoxicillin (875 mg) 2

Evidence Quality and Controversies

While penicillin has historically been the gold standard treatment, some studies suggest increasing failure rates (up to 30%) 4. More recent evidence indicates that cephalosporins and amoxicillin may provide better symptom resolution in some cases 3, 5. However, guidelines still recommend penicillin as first-line therapy due to its narrow spectrum, proven efficacy, safety, and low cost 1.

The dosing frequency of penicillin is important - twice daily dosing appears to be as effective as four times daily, but once-daily dosing shows higher failure rates 6.

Follow-up throat cultures are not routinely indicated for asymptomatic patients who have completed appropriate therapy 1.