Prescribed medicine use and extent of off-label use according to age in a nationwide sample of Australian children
Schaffer AL., Bruno C., Buckley NA., Cairns R., Litchfield M., Paget S., Zoega H., Nassar N., Pearson SA.
Background: Medicine prescribing for children is impacted by a lack of paediatric-specific dosing, efficacy and safety data for many medicines. Objectives: To estimate the prevalence of medicine use among children and the rate of ‘off-label’ prescribing according to age at dispensing. Methods: We used population-wide primarily outpatient dispensing claims data for 15% of Australian children (0–17 years), 2013–2017 (n = 840,190). We estimated prescribed medicine use and ‘off-label’ medicine use according to the child's age (<1 year, 1–5 years, 6–11 years, 12–17 years) defined as medicines without age-appropriate dose recommendations in regulator-approved product information. Within off-label medicines, we also identified medicines with and without age-specific dose recommendations in a national prescribing guide, the Australian Medicines Handbook Children's Dosing Companion (AMH CDC). Results: The overall dispensing rate was 2.0 dispensings per child per year. The medicines with the highest average yearly prevalence were systemic antibiotics (435.3 per 1000 children), greatest in children 1–5 years (546.9 per 1000). Other common medicine classes were systemic corticosteroids (92.7 per 1000), respiratory medicines (91.2 per 1000), acid-suppressing medicines in children <1 year (47.2 per 1000), antidepressants in children 12–17 years (40.3 per 1000) and psychostimulants in children 6–11 years (27.0 per 1000). We identified 12.2% of dispensings as off-label based on age, but 66.3% of these had age-specific dosing recommendations in the AMH CDC. Among children <1 year, off-label dispensings were commonly acid-suppressing medicines (35.5%) and topical hydrocortisone (33.1%); in children 6–11 years, off-label prescribing of clonidine (16.0%) and risperidone (13.1%) was common. Off-label dispensings were more likely to be prescribed by a specialist (21.7%) than on-label dispensings (7.5%). Conclusions: Prescribed medicine use is common in children, with off-label dispensings for medicines without paediatric-specific dosing guidelines concentrated in classes such as acid-suppressing medicines and psychotropics. Our findings highlight a need for better evidence to support best-practice prescribing.