What is the recommended evaluation and treatment for acute pharyngitis in adults and children?

Treatment of Acute Pharyngitis

Diagnostic Approach

The cornerstone of managing acute pharyngitis is to identify Group A Streptococcus (GAS) through laboratory testing rather than clinical features alone, because GAS is the only common bacterial cause requiring antibiotics and represents only 5-15% of adult cases and 20-30% of pediatric cases. 1

When to Test

• Perform testing when patients present with features suggesting bacterial infection: sudden-onset sore throat, fever, tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of viral features 1

• Do NOT test when clear viral features are present: cough, rhinorrhea, hoarseness, conjunctivitis, or oral ulcers—these strongly indicate viral etiology and testing leads to unnecessary identification of asymptomatic carriers 1, 2

• Do NOT test children under 3 years old, as GAS pharyngitis and acute rheumatic fever are rare in this age group, except when an older sibling has confirmed GAS infection 1

Testing Strategy by Age

Children and Adolescents:

• Use rapid antigen detection test (RADT) first 1
• Always back up negative RADT with throat culture because RADT sensitivity is only 80-90%, missing 10-20% of true infections 1
• Positive RADT does not require culture confirmation due to high specificity (≥95%) 1

Adults:

• RADT alone is sufficient—negative results do NOT require backup throat culture 1
• This is justified because adults have only 5-10% prevalence of GAS pharyngitis and extremely low risk of acute rheumatic fever 1, 3

Treatment of Confirmed GAS Pharyngitis

Penicillin or amoxicillin for 10 days is the definitive first-line treatment based on narrow spectrum, low adverse effects, and proven efficacy in preventing acute rheumatic fever when started within 9 days of symptom onset. 1

First-Line Antibiotics

• Penicillin V: 250 mg 2-3 times daily for children <27 kg; 500 mg 2-3 times daily for children ≥27 kg and adults, for 10 days 1
• Amoxicillin: 50 mg/kg once daily (maximum 1 g) for 10 days 1
• Benzathine penicillin G: Single intramuscular dose—600,000 U for patients <27 kg; 1,200,000 U for patients ≥27 kg 1

Penicillin-Allergic Patients

• Non-anaphylactic allergy: First-generation cephalosporin for 10 days 1
• Anaphylactic/immediate hypersensitivity:
  • Clindamycin 20 mg/kg/day divided in 3 doses (maximum 1.8 g/day) for 10 days 1
  • Azithromycin 12 mg/kg once daily (maximum 500 mg) for 5 days 1
  • Clarithromycin 15 mg/kg/day divided twice daily for 10 days 1

Management of Negative Test Results

Withhold antibiotics entirely and provide only symptomatic treatment when tests are negative for GAS, as the vast majority of these cases are viral and self-limited. 1, 3

Symptomatic Treatment

• Analgesics/antipyretics: Acetaminophen or ibuprofen for pain and fever relief 3, 2
• Avoid aspirin in children due to Reye's syndrome risk 2
• Throat lozenges for comfort 3
• Reassurance that symptoms typically resolve in less than 1 week 3

If Culture Pending in Children

• Provide symptomatic treatment while awaiting culture results 3
• If culture returns positive, initiate antibiotics—treatment within 9 days still prevents acute rheumatic fever 3
• Antibiotics shorten symptom duration by only 1-2 days, so delayed treatment does not compromise outcomes 3

Common Pitfalls to Avoid

• Do NOT treat based on clinical appearance alone without laboratory confirmation—physicians consistently overestimate the probability of GAS, and white patches/exudates occur with viral infections 1, 3

• Do NOT test or treat asymptomatic household contacts prophylactically—up to one-third of households include asymptomatic GAS carriers, and prophylaxis does not reduce subsequent infection rates 1, 3

• Do NOT perform follow-up testing after completing appropriate antibiotic treatment in asymptomatic patients—positive post-treatment tests may simply reflect carrier status, not treatment failure 1, 3

• Do NOT prescribe antibiotics for viral pharyngitis—they provide no benefit, contribute to resistance, and carry risk of adverse effects 3, 2

Special Circumstances

• Recurrent pharyngitis: Consider whether patient is a chronic GAS carrier experiencing recurrent viral infections rather than true recurrent GAS infections 1

• Outbreaks in closed settings: Test all symptomatic patients during documented outbreaks in schools, military barracks, or daycare centers 4

• Scarlet fever: This is simply GAS pharyngitis with a characteristic rash—diagnose and treat identically to GAS pharyngitis 4

• Persistent symptoms beyond 3-4 days: Consider suppurative complications (peritonsillar abscess) or alternative diagnoses, but do not retest if initial test was negative 3