Small Children Receive Large Doses, While Large Children Receive Low Doses of Amoxicillin Per kg.

Purpose: With increasing pneumococcal penicillin resistance, physicians treat pneumococcal infections with high-dose amoxicillin (80-90 mg/kg/d). High-dose amoxicillin approaches adult doses which makes clinicians reluctant to exceed "adult doses." This study examines the disparity of amoxicillin dosing between the ages of children.

Methods: A retrospective chart review of 5503 children prescribed amoxicillin regardless of diagnosis. The final cohort consisted of 3620 encounters with infections that align with recommendations of high-dose amoxicillin.

Results: Linear regression demonstrated a significant negative correlation between age/dose (mg/kg/d) and weight/dose (mg/kg/d). Larger children are prescribed declining doses in mg/kg/d, so most patients above 60 kg are dosed at less than 40 mg/kg/d. Children 6 years and under cluster around the 80 mg/kg/d dose.

Conclusions: Older children receiving a lower than recommended dose per kilogram of amoxicillin for conditions that require high-dose amoxicillin. There is a disparity in the dosing of amoxicillin between age/weight categories.

Article summary: A chart review of 3620 pediatric patient encounters prescribed amoxicillin. After controlling for weight, as age and weight increases, the dose of amoxicillin prescribed decreases. Children are reaching the adult maximum dose right after they surpass 15 kg.What is known on this subject: An Amoxicillin guideline shift to 80 to 90 mg/kg/d for treating pneumococcal infections in 2014. This was due to increasing intermediate penicillin resistance. Obesity results in children reaching the "maximum" doses at younger ages as well.What this study adds: There is a disparity is amoxicillin dosing among the pediatric population, are small children getting too much amoxicillin, or are larger children getting too little? Children are also reaching the adult maximum dose at low weights, such as 20 kg.Deidentified individual participant data will not be made available.