What is the normal course of treatment for strep throat?

Treatment for Strep Throat

Penicillin remains the treatment of choice for strep throat (group A streptococcal pharyngitis) due to its proven efficacy, safety, narrow spectrum, and low cost. 1

First-line Treatment Options

• Oral Penicillin V is the standard treatment for strep throat 1:

  • Children: 250 mg twice or three times daily for 10 days 1
  • Adolescents and adults: 250 mg three or four times daily OR 500 mg twice daily for 10 days 1

• Intramuscular Benzathine Penicillin G is preferred for patients who are unlikely to complete the full 10-day course of oral therapy 1:

  • Standard dose: 1.2 × 10^5 units as a single dose 1

• Amoxicillin is often used in place of oral penicillin V for young children due to better taste acceptance, with equal efficacy 1, 2

Treatment for Penicillin-Allergic Patients

• Erythromycin is the recommended alternative for patients with penicillin allergy 1, 3:

  • Erythromycin estolate: 20-40 mg/kg/day divided twice or three times daily for 10 days 1
  • Erythromycin ethyl succinate: 40 mg/kg/day divided twice or three times daily for 10 days 1

• First or second-generation cephalosporins are acceptable alternatives for patients who do not exhibit immediate hypersensitivity to β-lactam antibiotics 1, 4

• Clindamycin is recommended for patients with severe penicillin allergies (anaphylaxis, angioedema, respiratory distress, or urticaria) 1, 4

Treatment Duration

• Standard duration is 10 days for most oral antibiotics to achieve maximal pharyngeal eradication of group A streptococci 1

• While some newer agents (azithromycin, cefuroxime, cefixime, cefpodoxime) have been used for shorter courses (≤5 days), definitive results from comprehensive studies are not available, and these shorter courses cannot be recommended at this time 1, 5

Management of Treatment Failures

• A small percentage of patients will have recurrences of acute pharyngitis with positive cultures for group A streptococci shortly after completing treatment 1

• Treatment options for recurrences include:

  • Retreatment with the same antimicrobial agent used initially 1
  • If previously treated with oral agents and compliance is questionable, consider intramuscular benzathine penicillin G 1
  • For multiple recurrences, clindamycin or amoxicillin/clavulanate may be beneficial as they have shown high rates of pharyngeal eradication in these circumstances 1, 6

Common Pitfalls to Avoid

• Inadequate treatment duration: The full 10-day course must be completed to prevent complications such as rheumatic fever, even if symptoms improve earlier 7, 6

• Inappropriate antibiotic selection: Sulfonamides and tetracyclines should not be used due to higher resistance rates and frequent failure to eradicate even susceptible organisms 1

• Unnecessary follow-up testing: Routine post-treatment throat cultures are not recommended for asymptomatic patients who have completed therapy 1

• Dosing frequency errors: Once-daily dosing of penicillin is less effective than twice or four times daily dosing 8

• Treating without confirmation: A positive throat culture or rapid antigen detection test (RADT) should confirm the diagnosis before treatment; a negative RADT should be followed by a throat culture 1, 3

Special Considerations

• For patients with multiple treatment failures, consider alternative diagnoses or the possibility of a streptococcal carrier state with concurrent viral infections 1

• The risk of cross-reactivity between penicillins and cephalosporins is lower than previously thought, especially with later-generation cephalosporins 4

• Bacteriologic failure rates with penicillin therapy have increased over time and are now reported to be approximately 30%, primarily due to lack of compliance with the 10-day regimen 6