Potential medication dosing errors in outpatient pediatrics

Objective To determine the prevalence of potential dosing errors of medication dispensed to children for 22 common medications. Study design Using automated pharmacy data from 3 health maintenance organizations (HMOs), we randomly selected up to 120 children with a new dispensing prescription for each drug of interest, giving 1933 study subjects. Errors were defined as potential overdoses or potential underdoses. Error rate in 2 HMOs that use paper prescriptions was compared with 1 HMO that uses an electronic prescription writer. Results Approximately 15% of children were dispensed a medication with a potential dosing error: 8% were potential overdoses and 7% were potential underdoses. Among children weighing <35 kg, only 67% of doses were dispensed within recommended dosing ranges, and more than 1% were dispensed at more than twice the recommended maximum dose. Analgesics were most likely to be potentially overdosed (15%), whereas antiepileptics were most likely potentially underdosed (20%). Potential error rates were not lower at the site with an electronic prescription writer. Conclusions Potential medication dosing errors occur frequently in outpatient pediatrics. Studies on the clinical impact of these potential errors and effective error prevention strategies are needed.