Amoxicillin-Clavulanate Dosing for Adult Tonsillitis
For an adult with tonsillitis, the recommended dose of amoxicillin-clavulanate is 500 mg/125 mg every 8 hours OR 875 mg/125 mg every 12 hours for 7-10 days. 1, 2
Standard Dosing Regimen
The FDA-approved dosing for respiratory tract infections in adults is one 875 mg/125 mg tablet every 12 hours OR one 500 mg/125 mg tablet every 8 hours. 2
For mild to moderate tonsillitis without risk factors, the standard dose of 500 mg amoxicillin/125 mg clavulanate every 8 hours is appropriate. 1
Treatment duration is typically 7-10 days for complete resolution of tonsillitis. 1
When to Use High-Dose Therapy
Consider high-dose amoxicillin-clavulanate (2000 mg/125 mg twice daily) if the patient has ANY of these risk factors: 1, 3
Age over 65 years 3
Recent hospitalization 3
Geographic area with high prevalence (>10%) of penicillin-resistant Streptococcus pneumoniae 1, 3
Moderate to severe symptoms or systemic toxicity 3
The high-dose regimen achieves 90-92% predicted clinical efficacy against resistant pathogens, compared to 83-88% for standard dosing. 3
Administration Guidelines
Amoxicillin-clavulanate should be taken at the start of a meal to enhance absorption of clavulanate and minimize gastrointestinal side effects. 2
The medication may be taken without regard to meals, but starting with food is preferred for tolerability. 2
Clinical Evidence Supporting Use in Tonsillitis
A study of 30 adults with recurrent tonsillitis treated with amoxicillin-clavulanate 500 mg/125 mg three times daily for 10 days showed eradication of Group A streptococci in 6 of 7 patients (86%), with all but one patient cured at day 11-12. 4
In a large trial of 774 patients with recurrent pharyngotonsillitis, amoxicillin-clavulanate 1 g twice daily achieved 85.2% clinical cure at day 12 and 95.7% cure at 3-month follow-up. 5
The treatment was well tolerated, with digestive system adverse events (mainly diarrhea) occurring in 5.6-10.5% of patients. 5
Critical Dosing Considerations
Do NOT substitute two 250 mg/125 mg tablets for one 500 mg/125 mg tablet - they contain the same amount of clavulanate (125 mg each), making the substitution inappropriate. 2
The 250 mg/125 mg tablet and 250 mg/62.5 mg chewable tablet are NOT interchangeable due to different clavulanate content. 2
Reassessment Protocol
If no improvement or worsening occurs after 72 hours, reevaluate the diagnosis and consider changing antibiotics. 1
Clinical improvement should be evident within 48-72 hours of starting therapy. 1