Pooled data from 13 trials indicate that the drug Strattera, known technically as atomoxetine, continues to work well for teens with attention deficit/hyperactivity disorder (ADHD) over at least two years, with no surprise side effects.

In comments to Reuters Health, Dr. Timothy E. Wilens from Massachusetts General Hospital, Boston, said: “Given that atomoxetine is relatively new to the market, our longer term findings in adolescents are reassuring in that the medication continues to be effective without evidence of tolerance and is well tolerated without any unforeseen side effects emerging with chronic use.”

Wilens and colleagues note in the Journal of Pediatrics that young children with ADHD are often treated with the stimulant drug Ritalin, but Strattera, a nonstimulant, has appeal for use in older children and adolescents with ADHD; it is dosed once daily, limited abuse potential, and has a long duration of action.

The researchers report on 601 subjects 12 to 18 years of age treated with Strattera in clinical trials. Of these, 219 completed at least 2 years of treatment.

According to the authors, Strattera produced “significant improvement” in ADHD symptoms over the first 3 months of treatment, and symptoms remained improved up to 2 years without the need to up the dose of the drug.

During the 2-year period, 99 subjects (16.5 percent) stopped taking Strattera due to lack of effectiveness and 31 (5.2 percent) discontinued treatment due to side effects.

Mirroring past studies, the most frequently cited reasons for discontinuation were nausea, stomach ache, and headache. There was no evidence of height or weight growth deficits in adolescents treated for up to 2 years with Strattera.

Recently, two cases of liver injury related to Strattera were reported among the roughly 2.4 million patients who have used the drug to date, the team notes. In the current study, there were no “clinically significant” liver function test abnormalities.

“Despite the increasing recognition of the persistence of ADHD into adolescence, there remains a paucity of treatment data in this age group,” Wilens and colleagues write. The results of this investigation support the longer-term use of Strattera in adolescents with ADHD, they conclude.

The study was supported by Eli Lilly and Company of Indianapolis, Indiana, maker of Strattera.

SOURCE: Journal of Pediatrics, July 2006.