145 - Small Children Receive Large Doses of Amoxicillin per kg, while Large Children Receive Small Doses of Amoxicillin per kg for Otitis Media, Sinusitis, and Pneumonia

Publication Number: 145.6555

Katelyn S. Stenger, University of Hawaii, John A. Burns School of Medicine, Honolulu, HI, United States; Loren G. Yamamoto, University of Hawaii, John A. Burns School of Medicine, Honolulu, HI, United States

Background: With increasing pneumococcal penicillin resistance, physicians are recommended to treat pneumococcal infections with high-dose amoxicillin (80-90 mg/kg/day) rather than the standard dose (20-40 mg/kg/day). High dose amoxicillin in children approaches adult doses beginning at age 4 years which can make clinicians reluctant to exceed “adult doses” in young children.

Objective: This study aims to examine the disparity of amoxicillin dosing between the ages of children.

Design/Methods: A retrospective chart review of patients under 19 years prescribed amoxicillin from 2021-2023 from a metropolitan hospital system. The data set started with 5,503 patient encounters consisting of children prescribed Amoxicillin regardless of diagnosis. Patient encounters were excluded for incomplete charts, doses greater than 170 mg/kg/day, or diagnoses that recommended a low dose. 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/day), and weight/dose (mg/kg/day). Larger children show a wider scatter and are prescribed declining doses in mg/kg/day, such that most patients above 60 kg are dosed at less than 40 mg/kg/day. Children 6 years and under cluster around the 80 mg/kg/day dose.

Conclusion(s): Older children are receiving a significantly lower than recommended dose per kilogram of amoxicillin compared to younger age groups for conditions that require high dose amoxicillin. There is a disparity in the dosing of Amoxicillin between age/weight categories.

Box plot of amoxicillin dosing in each dosing group
box plot doses by age.pdfThis box plot of amoxicillin dosing by age shows that older children are receiving a lower dose of amoxicillin compared younger children who are getting a high dose of amoxicillin.

Daily amoxicillin doses per mg/kg/day by age
Linear regression dose and age.pdfThere is a negative linear relationship between the dose of amoxicillin prescribed and age of the patient, showing that a decrease in the dose prescribed is associated with an increase in age.

Daily amoxicillin doses per per mg/kg/day by weight (kg)
Linear regression dose and weight.pdfThis graph shows a linear negative relationship between the dose of amoxicillin prescribed and the weight of the patient. This is showing a decrease in the dose of amoxicillin is associated with an increase in the weight of the patient.

Box plot of amoxicillin dosing in each dosing group
box plot doses by age.pdfThis box plot of amoxicillin dosing by age shows that older children are receiving a lower dose of amoxicillin compared younger children who are getting a high dose of amoxicillin.

Daily amoxicillin doses per mg/kg/day by age
Linear regression dose and age.pdfThere is a negative linear relationship between the dose of amoxicillin prescribed and age of the patient, showing that a decrease in the dose prescribed is associated with an increase in age.

Daily amoxicillin doses per per mg/kg/day by weight (kg)
Linear regression dose and weight.pdfThis graph shows a linear negative relationship between the dose of amoxicillin prescribed and the weight of the patient. This is showing a decrease in the dose of amoxicillin is associated with an increase in the weight of the patient.