What is the recommended treatment for acute tonsillitis, including antibiotic options for Group A streptococcal infection and supportive care for viral cases?

Treatment of Acute Tonsillitis

For acute tonsillitis, treat with antibiotics only if Group A Streptococcus (GAS) is confirmed by testing; otherwise, provide supportive care alone, as most cases are viral. 1

Diagnostic Approach

Before initiating treatment, determine the likelihood of bacterial infection:

• Use a clinical scoring system (Centor or McIsaac score) to estimate the probability of GAS infection rather than relying on clinical judgment alone 1, 2
• Test patients with scores ≥3 using rapid antigen detection test (RADT) and/or throat culture to confirm GAS pharyngitis 1, 3
• Look specifically for: persistent fever, anterior cervical adenitis, tonsillopharyngeal exudates, and absence of cough 1
• Do not perform routine blood tests, ASLO titers, or other antistreptococcal antibody testing for acute tonsillitis—these have no diagnostic value 3

The IDSA guidelines emphasize that 70-95% of tonsillitis cases are viral, making selective testing critical to avoid unnecessary antibiotic use 4.

Treatment for Confirmed GAS Tonsillitis

When GAS is confirmed by testing:

First-Line Antibiotic Therapy

• Oral penicillin V (phenoxymethylpenicillin) for 10 days is the first-line treatment 5, 3
• This regimen provides adequate duration to eradicate GAS from the pharynx 1
• Penicillin V is associated with fewer additional physician visits compared to other antibiotics 6

Alternative Antibiotic Options

For penicillin allergy or intolerance:

• Macrolides (e.g., erythromycin) 3
• Oral cephalosporins (e.g., cefadroxil, cephalexin) 3

For penicillin treatment failure or frequent recurrences:

• Oral cephalosporins are indicated when more reliable GAS eradication is needed 3
• Amoxicillin shows decreased odds of developing complications (peritonsillar abscess, retropharyngeal abscess) compared to other antibiotics 6

Important Caveats

• Antibiotics shorten symptom duration by only 1-2 days, with number needed to treat of 6 at 3 days and 21 at 1 week 1
• The primary benefit is preventing complications (acute rheumatic fever, peritonsillar abscess, spread of infection), not symptom relief 1
• Do not routinely retest after treatment completion—this is no longer recommended 5

Treatment for Viral Tonsillitis

For patients without confirmed GAS (negative testing or low clinical probability):

Supportive Care Measures

• Analgesics: aspirin, acetaminophen, or NSAIDs for pain relief 1
• Throat lozenges for symptomatic relief 1
• Hydration 7
• Salt water gargles and viscous lidocaine may be used, though evidence is limited 1

Reassure patients that typical sore throat duration is less than 1 week and antibiotics are not needed for viral infections 1.

Management of Chronic GAS Carriers

If a patient has recurrent positive tests but no active immunologic response:

• Do not treat chronic carriers routinely with antibiotics—they are unlikely to spread infection and have very low risk of complications 5
• Chronic carriers may have intercurrent viral infections that mimic acute streptococcal pharyngitis 5

Special Situations Requiring Carrier Treatment

Consider eradication therapy only in specific circumstances 5:

• Community outbreak of acute rheumatic fever, glomerulonephritis, or invasive GAS
• Outbreak in closed/partially closed community
• Family or personal history of acute rheumatic fever
• Family with excessive anxiety about GAS infections
• When tonsillectomy is being considered solely for carriage

For carrier eradication, use clindamycin 20-30 mg/kg/day in 3 doses for 10 days (maximum 300 mg/dose) or combination regimens listed in IDSA guidelines 5.

Role of Tonsillectomy

• Tonsillectomy is NOT recommended solely to reduce frequency of GAS pharyngitis in adults or children 5, 1
• Consider tonsillectomy only for recurrent tonsillitis meeting specific criteria: ≥7 episodes in preceding year, ≥5 episodes per year for 2 years, or ≥3 episodes per year for 3 years 8
• Watchful waiting is strongly recommended if episodes fall below these thresholds 4

Common Pitfalls to Avoid

• Do not prescribe antibiotics based on clinical judgment alone without testing—over 60% of adults with sore throat receive unnecessary antibiotics 1
• Do not use IM benzathine penicillin as first-line therapy—it is associated with significantly more additional physician visits (IRR 1.46) compared to oral penicillin V 6
• Do not perform post-treatment testing unless patient has recurrent symptoms weeks or months later 5
• Do not confuse chronic carriers with acute infection—look for rising antistreptococcal antibody titers to distinguish active infection 5