A groundbreaking collaborative study conducted by researchers at the University of Turku and the University of Helsinki, in partnership with the Finnish Social Insurance Institution Kela, has illuminated critical insights regarding the long-term use of ADHD medications among children and adolescents in Finland. This nationwide register-based study reveals that the average duration for which young individuals remain on pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD) exceeds three years, a figure substantially longer than the one-year follow-up period for which robust safety data currently exists.
Over recent years, the prescription rates and utilization of ADHD medications have escalated considerably, reflecting a growing recognition of the disorder as well as changing clinical practices. Despite this increasing use, the comprehensive understanding of the long-term safety and neurodevelopmental impact of these medications remains insufficient. The Finnish research team delved into national health registers, harnessing data spanning 2008 to 2019, capturing nearly 41,000 children and adolescents who initiated ADHD medication within this timeframe. By applying advanced survival analysis techniques, specifically Kaplan-Meier estimations, they delineated the persistence and duration patterns of treatment.
One of the most striking patterns emerging from the data pertains to gender disparities and the influence of age at treatment initiation. It was observed that boys not only start treatment more frequently but also tend to remain on ADHD medication longer than girls. On average, boys experienced treatment durations exceeding those of girls by over a year. Moreover, earlier commencement of medication, particularly during the early school years, correlated with prolonged periods of pharmacotherapy across both genders.
The subgroup demonstrating the most extended treatment trajectories comprised boys aged between six and eight years at the onset of medication. In this cohort, the median treatment duration extended to over six years, with a substantial subset—25%—continuing treatment beyond nine years. Notably, this group also represented the largest proportion of individuals commencing ADHD medication, encompassing nearly one-third of all participants. Such prolonged pharmacological exposure during formative developmental phases raises important questions regarding neurobiological safety and functional outcomes.
Lead author Päivi Ruokoniemi, a Specialist in Clinical Pharmacology, Therapeutics, and Child Psychiatry at the University of Helsinki, underscores the critical gap in long-term evidence. Ruokoniemi highlights that while short-term efficacy and safety profiles of ADHD medications are supported by clinical trials with a minimum one-year follow-up mandated by the European Medicines Agency, the reality in clinical practice involves treatment durations several-fold longer. This mismatch between regulatory study durations and real-world treatment lengths underlines an urgent need for robust longitudinal investigations.
Current knowledge on the safety of extended ADHD medication use primarily stems from observational studies which, despite their value, are limited by methodological constraints such as confounding factors and lack of randomization. This impairs the capacity to establish clear causal relationships between long-term medication exposure and potential adverse neurocognitive or physical health outcomes. Consequently, there is a pressing need for controlled, long-duration clinical trials or innovative study designs capable of addressing these critical questions.
The researchers advocate for a cautious, evidence-informed approach to ADHD pharmacotherapy, emphasizing the primacy of non-pharmacological interventions as initial treatment strategies. When medication is deemed necessary, transparent communication regarding the benefits, risks, and existing uncertainties should be prioritized, tailored to the developmental stage and comprehension of both the child and caregivers. Furthermore, annual reassessment of the continued need for medication by a qualified medical professional is recommended to optimize therapeutic decisions and mitigate unnecessary prolonged exposure.
From a public health perspective, the study sheds light on significant trends in ADHD medication prevalence within Finland. In 2019, treatment coverage was estimated at approximately 5–6% among boys and 1.3–1.5% among girls in the relevant age groups. Despite this already substantial coverage, recent data imply that ADHD medication use has continued to rise post-study, paralleling global trends. Interestingly, this growth rate in Finland outpaces that seen in many other Nordic countries, intensifying concerns about long-term safety monitoring and responsible prescribing.
The meticulous register-based approach employed in this investigation capitalizes on the comprehensive Finnish healthcare data system, allowing unprecedented population-level analysis. The use of real-world data sources imparts external validity and practical relevance to the findings; however, it equally exposes the current lack of in-depth randomized controlled trials extending beyond one year—highlighting the paradox between clinical practices and scientific evidence.
Given the sensitive period of childhood and adolescent brain development, the protracted use of stimulant and non-stimulant ADHD medications prompts critical evaluation of potential impacts on neuroplasticity, cognitive maturation, cardiovascular health, and psychosocial functioning. Despite decades of clinical use, evidence gaps persist in understanding how chronic pharmacological intervention might modulate these complex developmental trajectories, warranting urgent scientific prioritization.
Moreover, the heterogeneity within ADHD presentations and individual responses to medication further complicates the risk-benefit calculus. Personalized medicine approaches, including pharmacogenomics and biomarker development, may offer future avenues to optimize treatment duration and minimize adverse effects. Until such tools become widely available, continuous vigilance, judicious prescribing, and thorough patient and family education remain foundational.
Published in the European Child & Adolescent Psychiatry journal in May 2025, this landmark study not only enhances epidemiological understanding but also provokes necessary discourse on regulation, clinical guidelines, and the ethical dimensions of treating vulnerable pediatric populations. It invites the scientific community, clinicians, policymakers, and patient advocates to collaboratively address the evident lacunae in long-term ADHD medication research.
In summary, while ADHD medications serve as a critical component of the therapeutic armamentarium, their long-term safety profile is insufficiently characterized relative to the duration they are commonly prescribed in routine clinical practice. This disparity underscores a pivotal challenge and opportunity for future research endeavors aimed at safeguarding the health and development of children and adolescents worldwide.
Subject of Research: Duration and safety of ADHD medication treatment in children and adolescents
Article Title: Duration of ADHD medication treatment among Finnish children and adolescents ‒ a nationwide register study
News Publication Date: 7-May-2025
Web References: https://doi.org/10.1007/s00787-025-02735-4
References: The study is published in the journal European Child & Adolescent Psychiatry.
Keywords: ADHD, medication duration, children, adolescents, long-term safety, pharmacotherapy, register study, Finland, neurodevelopment, clinical pharmacology, pediatric psychiatry
