What is the recommended treatment for strep throat?

Treatment of Strep Throat

Penicillin V (twice or three times daily for 10 days) or amoxicillin (twice daily for 10 days) are the recommended first-line antibiotics for confirmed Group A streptococcal pharyngitis due to proven efficacy, narrow spectrum, lack of resistance, and low cost. 1

When to Treat with Antibiotics

• Do not prescribe antibiotics for patients with 0-2 Centor criteria (fever, tonsillar exudates, tender anterior cervical adenopathy, absence of cough), as the modest benefits do not outweigh risks of side effects, antimicrobial resistance, and costs. 1

• For patients with 3-4 Centor criteria, discuss the modest benefits (1-2 days faster symptom resolution) against potential harms, as antibiotics provide limited clinical benefit even in confirmed streptococcal pharyngitis. 1

• Delayed prescribing (waiting >48 hours after initial consultation) is a valid strategy with no difference in complication rates compared to immediate treatment, allowing time for symptom resolution without antibiotics. 1

• Antibiotics reduce symptoms on day 3 (relative risk 0.72), but by 1 week, only confirmed Group A streptococcal-positive patients show benefit over placebo. 1

First-Line Antibiotic Choice

Penicillin V (Preferred)

• Penicillin V remains the treatment of choice: 500 mg twice or three times daily for 10 days in adults and adolescents. 1

• Twice-daily dosing is as efficacious as more frequent dosing and improves compliance, while once-daily penicillin shows 12 percentage points lower cure rates and should not be used. 2

• Group A streptococci have shown zero resistance to penicillin over five decades, maintaining its position as the gold standard. 1

Amoxicillin (Alternative First-Line)

• Amoxicillin 500 mg twice daily (or 875 mg twice daily for severe infections) for 10 days is equally effective to penicillin and preferred in young children due to better palatability of suspension formulations. 1, 3, 4

• In children, amoxicillin 40-50 mg/kg/day divided twice daily (maximum 1000 mg/day) shows superior bacteriologic cure rates (79.3% vs 54.5%) compared to standard-dose penicillin V, suggesting historical penicillin "failures" may reflect inadequate dosing. 5

• Avoid amoxicillin in older children and adolescents with suspected concurrent Epstein-Barr virus (infectious mononucleosis) due to risk of severe maculopapular rash; use first-generation cephalosporin or macrolide instead if streptococcal infection is documented. 1, 6

• Once-daily amoxicillin (50 mg/kg, maximum 1000 mg) for 10 days is FDA-approved and may enhance adherence, though this broader-spectrum approach is more expensive than penicillin. 1

Penicillin-Allergic Patients

Non-Immediate Hypersensitivity

• First-generation cephalosporins (cephalexin 500 mg four times daily or cefadroxil) for 10 days are preferred alternatives with cross-reactivity risk <3%. 1, 6

• Narrow-spectrum cephalosporins (cephalexin, cefadroxil) are strongly preferred over broad-spectrum agents (cefdinir, cefpodoxime) to minimize selection of resistant flora. 1

Immediate-Type Hypersensitivity (Anaphylaxis)

• Clindamycin 300 mg orally three times daily for 10 days is the preferred alternative, with only 1% resistance in the United States. 1, 6

• Macrolides (erythromycin or clarithromycin for 10 days, or azithromycin 12 mg/kg/day up to 500 mg for 5 days) are acceptable alternatives, though local resistance patterns should be considered. 1, 6

• Azithromycin 5-day courses are FDA-approved but more expensive and broader-spectrum than penicillin without clear clinical superiority. 1

Treatment Duration and Follow-Up

• Complete the full 10-day course regardless of symptom resolution to achieve maximal pharyngeal eradication and prevent acute rheumatic fever, particularly for any Group A streptococcal infection. 1, 6, 3

• Patients become non-contagious after 24 hours of appropriate antibiotic therapy. 6

• Do not perform routine follow-up throat cultures in asymptomatic patients after completing therapy, as asymptomatic carriage is common (>20% in school-aged children) and does not require treatment. 1, 6

Intramuscular Option

• Intramuscular benzathine penicillin G (single dose) is preferred for patients unlikely to complete 10-day oral therapy, ensuring full treatment delivery. 1

Critical Pitfalls to Avoid

• Never use tetracyclines, sulfonamides, trimethoprim-sulfamethoxazole, or older fluoroquinolones (ciprofloxacin) as they do not eradicate Group A streptococci or have high resistance rates. 1

• Cephalosporins show statistically superior bacteriologic cure rates compared to penicillin (OR 2.29-2.34), but the absolute differences are small (5-10%) and not clinically meaningful enough to justify routine use over penicillin given broader spectrum and higher cost. 1, 7

• Shorter courses (4-5 days) of cephalosporins are FDA-approved but cannot be endorsed due to methodological flaws in supporting studies, broader spectrum, and higher cost without clear benefit. 1

• Antibiotics do not need to be started immediately—treatment within 2-3 days of symptom onset still hastens recovery by 1-2 days, allowing time for diagnostic confirmation. 1

• In low-income countries and Aboriginal communities with high rheumatic fever risk, the risk-benefit calculation favors more liberal antibiotic use, though evidence is limited as most trials were conducted in high-income settings. 7