Summary: A large Finnish register study shows that many children—particularly boys who begin ADHD medication between ages 6 and 8—remain on treatment for multiple years. While the average duration of ADHD medication exceeded three years, 25% of treated children stayed on medication for more than seven years, and some for nearly a decade.
Despite growing and widespread use of these medicines, controlled clinical trial data on long-term safety extend only to one year. The researchers emphasize the need for more rigorous, long-term studies and recommend annual clinical reassessments. They urge caution when prescribing stimulant and non-stimulant ADHD medications to children at sensitive stages of development.
Key facts
- Prolonged use: One quarter of children remained on ADHD medication for more than seven years.
- Gender differences: Boys were more likely to start treatment earlier and remained on medication longer than girls.
- Evidence gap: No randomized controlled trials have demonstrated safety beyond one year of follow-up.
Source: University of Turku
Background: Use of ADHD medication has risen notably in recent years, but long-term effects in children remain insufficiently studied despite many years of clinical use.
This nationwide, population-based register study found that the median duration of ADHD medication among Finnish children and adolescents was slightly more than three years. Among the quarter of children with the longest treatment periods, medication use continued for over seven years.
“This study opens an important discussion because the real-world duration of ADHD medication among children and adolescents has been examined only to a very limited extent,” says study lead Päivi Ruokoniemi, a specialist in Clinical Pharmacology, Therapeutics and Child Psychiatry at the University of Helsinki.
Boys start earlier and stay on treatment longer
The analysis showed that both sex and the child’s age at treatment initiation significantly influence how long medication continues. On average, treatment lasted about one year longer for boys than for girls. Earlier age at the start of medication was associated with longer overall treatment duration for both sexes.
Boys who began medication between ages 6 and 8 had the longest durations. The median treatment time for this group was 6.3 years, and the longest 25% in this cohort were treated for more than 9.4 years. This youngest male group was also the largest single group initiating medication, accounting for 32.4% of the study population.
“Our findings indicate that a notable share of young children—especially boys—remain on ADHD medication for many years, often covering their entire primary school period. That is troubling because reliable clinical trial evidence on safety is available only up to one year of follow-up, and we are dealing with children in a critical period of development,” Ruokoniemi adds.
Long-term randomized evidence is lacking
Randomized, controlled clinical trials provide the most reliable evidence for medication safety. For regulatory approval in Europe, pharmaceutical companies must supply clinical safety data that include at least one year of follow-up for ADHD medications.
“Long-term effects have been examined in many observational and uncontrolled studies, but these designs are vulnerable to confounding and cannot firmly establish cause-and-effect relationships,” Ruokoniemi explains.
Because of these uncertainties, the researchers recommend that ADHD medication should generally be considered only after non-pharmacological interventions—such as behavioural approaches and educational supports—have been tried and judged insufficient.
When medication is started, caregivers and children should receive age-appropriate information about expected benefits, possible harms, and the limitations of current evidence. The authors also advise that any ongoing need for ADHD medication be reassessed by a physician at least annually.
The descriptive register study, published in the journal European Child & Adolescent Psychiatry, was a collaboration between the Universities of Turku and Helsinki and the Finnish Social Insurance Institution (Kela).
Researchers used data on reimbursable dispensations from the National Health Insurance Scheme for 2008–2019, covering nearly 41,000 children and adolescents who initiated ADHD medication during that period. Treatment duration was estimated with Kaplan–Meier survival analysis, allowing a gap of up to 365 days between recorded prescription purchases when defining a continuous treatment period. The median follow-up time was 3.8 years.
In 2019—the last year included in the study—the prevalence of ADHD medication use was approximately 5–6% among boys and 1.3–1.5% among girls. Since then, use has continued to rise both globally and in Finland, where increases have outpaced many neighboring countries.
“We are aware that the proportion of Finnish children and adolescents taking ADHD medication has already doubled since the period covered by this research,” Ruokoniemi notes.
About this psychopharmacology and ADHD research news
Author: Tuomas Koivula
Source: University of Turku
Contact: Tuomas Koivula – University of Turku
Image: Image credited to Neuroscience News
Original research (open access): “Duration of ADHD medication treatment among Finnish children and adolescents ‒ a nationwide register study” by Päivi Ruokoniemi et al., European Child & Adolescent Psychiatry. DOI: 10.1007/s00787-025-02735-4
Abstract
Duration of ADHD medication treatment among Finnish children and adolescents ‒ a nationwide register study
Aim
To examine how long children and adolescents (ages 6–18) in Finland remain on ADHD medication, and how treatment duration varies by sex and age group between 2008 and 2019.
Methods
This descriptive, population-based register study included all Finnish children and adolescents aged 6–18 who started their first ADHD medication between January 1, 2008 and December 31, 2019 (n = 40,691). Data were drawn from the National Health Insurance Scheme register of reimbursable dispensations. Treatment duration was defined from first to last recorded purchase, allowing gaps up to 365 days between purchases. Median follow-up time was 3.8 years, and Kaplan–Meier methods were used to estimate durations.
Results
The overall median duration of ADHD medication treatment was 3.2 years (95% CI 3.2–3.3). Sex and age at treatment initiation significantly affected duration (p < .0001 for both). Boys had longer treatment periods than girls, and younger starters used medication for longer. Boys who began treatment at ages 6–8 (32.4% of the cohort) showed the longest median duration at 6.3 years (95% CI 6.2–6.5), with the upper quartile exceeding 9.4 years.
Conclusions
In routine clinical practice, children’s ADHD medication treatment often continues well beyond the one-year follow-up typical of randomized trials, sometimes lasting several years—especially among boys who start treatment at a younger age. These findings highlight the need for stronger long-term safety data and for careful, ongoing clinical review of treatment necessity.