One-year prospective follow-up of pharmacological treatment in children with attention-deficit/hyperactivity disorder

To delineate the safety and tolerability profile of methylphenidate and atomoxetine in children and adolescents with attention deficit hyperactivity disorder (ADHD) monitored for more than 1 year. A cohort study analyzing data from the national ADHD register on patients from the Lombardy Region treated with MPH or atomoxetine. A total of 229 children (median age 11 years, range 6-17), enrolled in 15 regional centers between June 2007 and May 2010. The prevalence rate of pharmacological treatment for ADHD was 0.23%, whereas the estimated ADHD prevalence in the population was 0.95%. In total, 73.8% of patients had been treated with atomoxetine (10-90 mg daily) or MPH (10-75 mg daily); 22% of patients also received an additional psychotropic drug. Of the treated children, 26.9% discontinued the drug prior to 1 year of treatment, mostly because of adverse effects (28.6%). No new or unexpected adverse events (rate 39.2%) were encountered. Decreased appetite, headache, and unstable mood were the leading events. The most severe events occurred in two boys: one experienced absence seizures for the first time with MPH, the other experienced hallucinations with atomoxetine. Therapy was discontinued in ten male patients (7.7%) because of adverse events. All patients with adverse effects recovered well. A very low rate of ADHD prevalence was estimated in Italian children compared to that reported in other countries. Although the medications for ADHD are generally well tolerated, with only mild or minor adverse effects in most cases, their rational use can only be guaranteed by disseminating and monitoring evidence-based practices and by monitoring the safety and efficacy of treatments in both the short and long terms with appropriate tools and approaches.