Is treatment necessary for strep throat?

Treatment of Strep Throat

Yes, you must treat confirmed Group A streptococcal pharyngitis with antibiotics, but only after microbiologic confirmation—treatment is recommended to prevent serious complications including acute rheumatic fever, peritonsillar abscess, and to modestly reduce symptom duration. 1

When Treatment is Indicated

Antibiotics should only be prescribed for patients with confirmed Group A streptococcal pharyngitis through positive rapid antigen detection test (RADT) or throat culture. 1 The 2012 IDSA guidelines explicitly state that antibiotic therapy is recommended only for patients with a positive streptococcal test result. 1

Key Testing Requirements:

• Test patients with symptoms suggestive of Group A streptococcal pharyngitis (persistent fevers, anterior cervical adenitis, tonsillopharyngeal exudates) by RADT and/or culture before initiating antibiotics 1
• Clinical diagnosis alone has insufficient accuracy (≤80% predictive value even with scoring systems), making microbiologic confirmation essential 2
• Beta-hemolytic colonies alone are insufficient for treatment—specific Group A identification is required through latex agglutination, immunofluorescence, or serological grouping 2

Why Treatment is Necessary

Prevention of Complications (Primary Justification):

• Antibiotics reduce acute rheumatic fever to less than one-third (OR 0.30; 95% CI 0.20 to 0.45) 3
• Acute otitis media is reduced to about one-quarter (OR 0.22; 95% CI 0.11 to 0.43) 3
• Peritonsillar abscess (quinsy) is reduced (OR 0.16; 95% CI 0.07 to 0.35) 3
• Evidence suggests protection against acute glomerulonephritis, though data are limited 1, 3

Symptom Reduction (Secondary Benefit):

• Antibiotics shorten the duration of sore throat by approximately 1 to 2 days 1
• The number needed to treat to reduce symptoms is 6 after 3 days of treatment and 21 after 1 week 1
• Symptoms of headache, throat soreness, and fever are reduced by about half at 3.5 days 3
• This modest symptomatic benefit alone would not justify treatment—the primary rationale is complication prevention 1

Additional Benefits:

• Limits spread of Group A Streptococcus in outbreaks 1
• Permits earlier return to school or work 4
• Reduces duration of contagiousness 4

First-Line Treatment Regimen

Penicillin remains the drug of choice for non-allergic patients based on proven efficacy, safety, narrow spectrum, and low cost. 1

Recommended Dosing:

Adults and children ≥40 kg:

• Penicillin V: 250 mg orally twice daily for 10 days 1, 5
• Alternative: Penicillin V 500 mg orally every 8 hours for 10 days 1
• Intramuscular benzathine penicillin G is preferred for patients unlikely to complete 10-day oral therapy 1

Children <40 kg:

• Amoxicillin 25 mg/kg/day divided every 12 hours for 10 days (mild/moderate infections) 6
• Amoxicillin 45 mg/kg/day divided every 12 hours for 10 days (severe infections) 6
• Amoxicillin is often used in place of oral penicillin V for young children due to better palatability 1

Critical Duration Requirement:

Treatment must continue for at least 10 days to eradicate Group A Streptococcus from the pharynx and prevent acute rheumatic fever. 1, 6, 5 This 10-day minimum applies regardless of symptom resolution. 6, 5

Penicillin-Allergic Patients

For patients with penicillin allergy:

• First-generation cephalosporins (e.g., cephalexin) 1, 7
• Macrolides (e.g., erythromycin, azithromycin) 1, 7
• Clindamycin 1

Important caveat: Limited evidence suggests cephalosporins may have better eradication rates than penicillin (OR 0.51 for treatment failure; 95% CI 0.27 to 0.97), though this was not statistically significant in intention-to-treat analysis. 8 However, penicillin remains first-line due to cost, narrow spectrum, and lack of resistance. 8

When NOT to Treat

Asymptomatic Carriers:

• Do not treat chronic Group A Streptococcus carriers 1
• Carriers are at little or no risk for complications and unlikely to spread infection to close contacts 1
• Up to 20% of school-aged children may be asymptomatic carriers during winter and spring 1, 9
• Carriers have Group A streptococci present but no immunologic reaction to the organism 1, 9

Viral Pharyngitis:

• More than 60% of adults with sore throat receive antibiotics, yet most cases are viral 1
• Do not prescribe antibiotics for negative streptococcal tests 1
• Offer analgesic therapy (aspirin, acetaminophen, NSAIDs, throat lozenges) instead 1

Household Contacts:

• Do not routinely test or treat asymptomatic household contacts 1
• Exception: Consider testing contacts if there are repeated episodes suggesting "ping-pong" transmission 9

Common Pitfalls to Avoid

1. Empiric treatment without testing: Over 60% of sore throats receive antibiotics despite most being viral—always confirm diagnosis first 1

2. Stopping antibiotics early: Even if symptoms resolve in 2-3 days, the full 10-day course is essential to prevent rheumatic fever 1, 6, 5

3. Routine post-treatment testing: Do not perform follow-up cultures on asymptomatic patients who completed therapy 1, 9

4. Treating carriers: Repeated positive tests in asymptomatic patients likely represent carrier state, not treatment failure—do not retreat unless symptomatic 1, 9

5. Using ineffective antibiotics: Avoid tetracyclines, sulfonamides, trimethoprim-sulfamethoxazole, or older fluoroquinolones, which are not effective against Group A Streptococcus 9

Special Populations

In areas with high rheumatic fever prevalence (poor and crowded inner-city populations, low-income countries, Aboriginal communities where medical follow-up may be lacking):

• Intramuscular benzathine penicillin G is preferred over oral therapy to ensure compliance 4, 8
• The number needed to treat is much lower in these high-risk populations 8, 3

Patients with history of rheumatic fever:

• Post-treatment cultures are indicated due to unusually high risk for recurrence 9
• More aggressive follow-up is warranted 9