Methylphenidate is a stimulant medication used to treat attention deficit hyperactivity disorder (ADHD). Patients with ADHD are usually at a higher risk of seizures, but the effect of methylphenidate on the risk of seizures is not clear. This study aims to investigate the association between methylphenidate treatment and the risk of seizure.

This population-based observational study included a total of 29,604 patients aged 6-25 years who received at least one methylphenidate prescription during the study duration. The primary outcome of the study was the relative incidence of seizures between individuals exposed to methylphenidate and non-exposed periods.

Out of 29,604 total individuals who participated in the study, 269 had seizures. The findings suggested that the overall incidence of seizures in patients exposed to methylphenidate was 4.4 per 10 000 patient-years. Further analysis indicated that the risk of seizures was higher during the first 30 days of methylphenidate treatment, as compared with non-exposed periods (incident rate ratio 4.01). After 30 days of treatment, no significant risk of seizures was identified.

The research concluded that the incidence of seizures was higher during the first 30 days of the methylphenidate treatment. After 30 days, no risk was observed with the continuation of methylphenidate treatment.