ADHD stimulants match on effectiveness, differ in one important way

Clinical takeaway: Dexamphetamine and methylphenidate produced comparable ADHD symptom improvement and treatment persistence over 12 months, but children receiving dexamphetamine experienced substantially greater early weight loss, underscoring the importance of growth monitoring and consideration of baseline weight when selecting therapy.

As ADHD medication use continues to rise, clinicians often must choose between stimulant options without robust long-term comparative data. This randomized trial provides rare 12-month head-to-head evidence to help guide initial treatment selection.

In one of the few randomized, head-to-head stimulant comparisons with year-long follow-up, Australian investigators assigned 100 stimulant-naive children and adolescents with ADHD (mean age 9 years; 73% male) to immediate-release dexamphetamine or methylphenidate and tracked symptom response, treatment adherence, and growth outcomes for 12 months.

Both medications produced marked and sustained improvements in ADHD symptoms during the initial titration period, with no meaningful differences between groups across measures of inattention, hyperactivity, or oppositional behaviors. After 12 months, 68% of children originally assigned to methylphenidate and 56% assigned to dexamphetamine remained on their allocated stimulant, while medication changes due to appetite suppression, behavioral effects, or sleep problems occurred at comparable rates. Overall, 62% of participants continued their originally assigned treatment after 1 year.

The key distinction was weight change. Children treated with dexamphetamine lost an average of 1.4 kg during the first 3 months, compared with about 0.3 kg among those receiving methylphenidate. After 12 months, the methylphenidate group had gained about 1.3 kg relative to baseline, whereas the dexamphetamine group remained about 0.8 kg below baseline weight. Despite these differences, height growth was similar, with children in both groups gaining roughly 4.5 to 5 cm over the study period.

As lead author Dr. Alison Poulton noted, "Both medications worked equally well for improving ADHD symptoms, and a year later most children were still taking their original stimulant... The main difference was that children taking dexamphetamine experienced greater weight loss, which is an important consideration when choosing treatment and monitoring growth."

Source: Poulton A, et al. (2026 July 7) J Paediatr Child Health. A Randomised Open-Label Comparison of Dexamphetamine and Methylphenidate in Children With Attention Deficit Hyperactivity Disorder (ADHD): Symptom Response, Adherence and Weight Impact Over 12 Months