What is the dose of Augmentin (amoxicillin/clavulanate) 457/5 ml for a 3-year-old child weighing 22 kg with bacterial tonsillitis?

Augmentin 457/5 ml Dosing for Bacterial Tonsillitis in a 3-Year-Old, 22 kg Child

For this 3-year-old child weighing 22 kg with bacterial tonsillitis, administer 10 ml of Augmentin 457/5 ml (which provides 914 mg amoxicillin) twice daily for 10 days. 1, 2

Dosing Calculation and Rationale

The high-dose regimen of 90 mg/kg/day of amoxicillin divided into 2 doses is the appropriate choice for bacterial tonsillitis in this age group. 1, 2

• For a 22 kg child, the total daily amoxicillin dose should be: 22 kg × 90 mg/kg = 1,980 mg/day 1
• Divided into 2 doses: 990 mg per dose (approximately 1,000 mg per dose) 1
• The Augmentin 457/5 ml suspension contains 457 mg amoxicillin per 5 ml 1
• Therefore: 10 ml twice daily provides 914 mg per dose, which is appropriate for this weight 1, 2

Why High-Dose Therapy is Indicated

High-dose amoxicillin-clavulanate (90 mg/kg/day) is specifically recommended for bacterial pharyngitis/tonsillitis in children to ensure adequate coverage against Group A Streptococcus and potential resistant organisms. 1

• The high-dose formulation (14:1 ratio of amoxicillin to clavulanate) causes less diarrhea than standard formulations while maintaining superior efficacy 1
• This dosing achieves tissue concentrations adequate to overcome intermediately resistant Streptococcus pneumoniae and provides optimal coverage for Group A Streptococcus 1

Treatment Duration

The treatment duration should be 10 days for bacterial tonsillitis. 1, 2, 3

• Studies comparing 5-day amoxicillin/clavulanate with 10-day penicillin V showed comparable clinical efficacy, with bacteriologic eradication rates of 83% versus 77% respectively 3
• However, 10-day therapy remains the standard recommendation for streptococcal pharyngitis to ensure adequate bacterial eradication and prevent complications 1, 2

Administration Instructions

Administer at the start of meals to enhance clavulanate absorption and minimize gastrointestinal side effects. 2

• The medication may be taken without regard to meals, but absorption of clavulanate is enhanced when given at the start of a meal 2
• Taking with food significantly reduces the incidence of diarrhea, the most common adverse effect 2, 4

Common Pitfalls to Avoid

Do not substitute lower-dose formulations or use three-times-daily dosing for this indication. 1, 2

• The 125/31 mg per 5 ml suspension would require 35 ml three times daily to achieve adequate dosing, which is impractical and increases gastrointestinal side effects 1, 2
• Twice-daily dosing with the high-dose formulation (457/5 ml) provides equivalent efficacy with better compliance and fewer adverse effects compared to three-times-daily regimens 4
• Using subtherapeutic doses fails to achieve adequate tissue concentrations and promotes antimicrobial resistance 1

Expected Clinical Response

Clinical improvement should be evident within 48-72 hours of initiating therapy. 1

• If no improvement or worsening occurs after 72 hours, reassess the diagnosis and consider alternative pathogens or complications 1
• Most adverse events are mild-moderate gastrointestinal disturbances, with diarrhea occurring in approximately 7% of patients on twice-daily dosing 4