New study exposes gap between ADHD drug use and safety research in children

A new study from Finland has found that children with attention-deficit/hyperactivity disorder often stay on medication for several years, with the longest durations seen among younger boys. The research, published in the journal European Child & Adolescent Psychiatry, analyzed nationwide data and revealed that one in four children who start medication at age six to eight continue using it for at least nine years.

This large-scale study offers rare insight into the real-world patterns of ADHD treatment among children and teenagers, showing that many continue medication far longer than what clinical trials have typically examined. The findings raise important questions about the long-term benefits, safety, and management of medication-based treatment plans for ADHD in pediatric populations.

ADHD is one of the most common neurodevelopmental conditions diagnosed in childhood. It involves persistent patterns of inattention, impulsivity, and hyperactivity that interfere with everyday functioning. While medication is a widely used treatment option and has been shown to reduce symptoms in the short term, much less is known about how long children actually remain on these medications and what the long-term outcomes look like. Most clinical trials on ADHD medications only track children for several weeks or months.

The Finnish research team conducted the study to better understand how long children and adolescents stay on ADHD medication once treatment begins. They used administrative health data from the country’s national insurance system, which covers the entire population. Because the data included information on every reimbursed ADHD medication purchase, the researchers were able to follow nearly every child in Finland who began medication for ADHD over a 12-year period.

The study included 40,691 children and adolescents between the ages of 6 and 18 who started ADHD medication between 2008 and 2019. The average age of starting treatment was 9 years old, and over three-quarters of the participants were boys. The researchers excluded children under age 6, as medication is typically not recommended at that age, and removed cases where the medication might have been prescribed for a different condition like narcolepsy.

To estimate how long treatment lasted, the researchers calculated the time between a child’s first and last medication purchases, allowing for gaps of up to one year to account for the stop-and-start nature of some treatment plans. The team found that the overall median duration of treatment was 3.2 years. That means half of the children continued medication for longer than that, and half stopped earlier.

The study found that both age and sex played a role in how long children stayed on medication. Boys had longer treatment durations than girls, and younger children tended to remain on medication longer than those who started treatment as teenagers. Among all groups, boys who began treatment between the ages of 6 and 8 had the longest median duration of use: 6.3 years. In this group, one in four continued treatment for more than 9 years.

Children who started treatment later in adolescence were more likely to stop sooner. For example, those who started medication between ages 13 and 15 were 3.6 times more likely to stop treatment than those who began at ages 6 to 8. Teens aged 16 to 18 were nearly four times more likely to discontinue medication than the youngest group.

These patterns remained consistent even after the researchers performed additional analyses to rule out the influence of changing clinical practices over time or possible misclassification of treatment gaps. The results suggest a robust trend: younger children, particularly boys, tend to remain on medication for longer periods.

These findings are significant because they highlight a gap between clinical research and real-world treatment. Most randomized trials for ADHD medication only examine short-term effects, often lasting just a few months. Yet in everyday practice, many children—especially those who begin treatment early—are using these medications for the better part of a decade. This raises questions about whether current research provides enough information on the long-term safety and effectiveness of ADHD medications.

Although some studies suggest that ADHD medication can help reduce academic struggles, behavioral problems, and even accidents, the evidence is mixed when it comes to psychological well-being or long-term developmental outcomes. Moreover, there are concerns about possible side effects from extended use of stimulant medications, such as appetite suppression, sleep disturbances, and effects on growth.

Some prior research has suggested that long-term use of stimulant medication might be linked to slower growth in height during childhood. For instance, findings from the Multimodal Treatment Study of ADHD indicated a small but persistent reduction in adult height among those who remained on high doses for many years. However, other studies have not found statistically significant changes, and many experts agree that more research is needed to understand these potential risks fully.

This new Finnish study emphasizes the need for long-term monitoring and follow-up of children receiving ADHD medication. Clinical guidelines already recommend regular reassessment of treatment plans, especially as children age and their symptoms change. Some children may no longer need medication, while others may benefit from adjustments in dosage or added behavioral interventions.

The researchers also noted that several local factors might influence treatment continuation in Finland. These include educational reforms that increased the use of digital devices in schools and the shortage of child psychiatrists with training in neurodevelopmental conditions. Both factors could affect how ADHD is identified, diagnosed, and treated.

Interestingly, the study found that boys in Finland are much more likely to receive ADHD medication than girls, a trend also seen in other Nordic countries. The reasons for this are not entirely clear but may reflect differences in how symptoms present, how parents and teachers respond to behaviors, or even how healthcare providers diagnose and treat the condition.

While the study used comprehensive national data, it had some limitations. The researchers did not have access to detailed clinical information such as symptom severity, co-occurring conditions, or whether children also received behavioral therapies. They also relied on prescription records as a proxy for actual medication use, which may not always align perfectly with adherence.

But the findings still offer important insight into the long-term use of ADHD medication in a real-world setting. They suggest that many children—especially those who begin treatment at a younger age—remain on medication far longer than what most studies have examined. This underscores the need for more robust, long-term safety studies and better support systems to help clinicians and families make informed decisions about continuing or stopping treatment.

The study, “Duration of ADHD medication treatment among Finnish children and adolescents ‒ a nationwide register study,” was authored by Terhi A. Kolari, Miika Vuori, Hanna Rättö, Eveliina A. Varimo, Eeva T. Aronen, Kari Auranen, Leena K. Saastamoinen, and Päivi T. Ruokoniemi.