Objective: The aim of this study was to determine the frequency of off-label prescribing to children at United States outpatient visits and to determine how drug class, patient age, and physician specialty relate to off-label prescribing.
Methods: Data from the 2001 through 2004 National Ambulatory Medical Care Surveys (NAMCS) consisted of a sample of 7901 outpatient visits by children aged 0 through 17 years in which prescriptions were given, representative of an estimated 312 million visits. We compared FDA-approved age and indication to the child's age and diagnoses. We used multivariate logistic regression to determine adjusted differences in probabilities of off-label prescribing.
Results: Sixty-two percent of outpatient pediatric visits included off-label prescribing. Approximately 96% of cardiovascular-renal, 86% of pain, 80% of gastrointestinal, and 67% of pulmonary and dermatologic medication prescriptions were off label. Visits by children aged <6 years had a higher probability of off-label prescribing (P < .01), especially visits by children aged <1 year (74% adjusted probability). Visits to specialists also involved a significantly increased probability (68% vs 59% for general pediatricians, P < .01) of off-label prescribing.
Conclusions: Despite recent studies and labeling changes of pediatric medications, the majority of pediatric outpatient visits involve off-label prescribing across all medication categories. Off-label prescribing is more frequent for younger children and those receiving care from specialist pediatricians. Increased dissemination of pediatric studies and label information may be helpful to guide clinical practice. Further research should be prioritized for the medications most commonly prescribed off label and to determine outcomes, causes, and appropriateness of off-label prescribing to children.