Prescription of inhaled corticosteroid in children before, during, and after the COVID-19 pandemic: time trends and regional differences in Norway

Abstract Background Inhaled corticosteroids (ICSs) are the basic treatment for asthma, but prescription rates are markedly higher in preschool children than older children, a pattern not explained by asthma prevalence. This study examined time trends in ICSs prescription rates in Norwegian children before, during, and after the COVID-19 pandemic. Methods Annual data (2013–2025) on children with at least one dispensed ICSs prescription were obtained from the Norwegian Prescribed Drug Registry (NorPD), stratified by age group (0–4, 5–9, 10–14 years), sex, and county. For 2019–2022 we obtained monthly data. Rates per 1000 children were estimated using Poisson regression. Results Among children aged 0–4 years, prescription rates declined slightly before the Covid-19 pandemic, declined a further 19% in 2020, rose above pre-pandemic levels by 2022, then declined again through 2025. Rates in 5–9-year-olds were stable through the pandemic but rose significantly from 2021 to 2024. Rates in 10–14-year-olds remained stable, with a moderate increase from 2022. Monthly data showed a sharp pandemic-onset rise in March 2020 followed by markedly low rates in young children, then pronounced winter peaks in subsequent seasons. Regional variation was substantial, greatest in the youngest group (> 3-fold between counties), the variations were largely consistent over time. Conclusion ICS prescription rates in Norwegian children vary substantially by age, season, year, and region, particularly in children 0–4 years. These patterns suggest ICS may be overprescribed for infection-related respiratory symptoms in young children, while recent trends may also reflect improved guideline adherence.