TORONTO – Reducing the dose of atomoxetine may be possible for children with attention-deficit hyperactivity disorder who have responded well to the medication, Dr. Jeffrey Newcorn reported in a poster at the joint annual meeting of the American Academy of Child and Adolescent Psychiatry and the Canadian Academy of Child and Adolescent Psychiatry.
Dr. Newcorn, of the Mount Sinai Medical Center, New York, investigated low-dose response rates in 229 children aged 6–16 years who had responded well to atomoxetine (Strattera) doses of up to 1.8 mg/kg per day in a previous trial. These children were randomized to continue their same dose of atomoxetine (mean 1.43 mg/kg per day) or to take a reduced dose (mean 0.46 mg/kg per day), and were followed for up to 8 months.
Only three children in the previous-dose group (2.6%) and three (2.5%) in the low-dose group relapsed. However, significantly more children in the low-dose group were no longer considered medication responders; i.e., they no longer had a symptom reduction of at least 40%. The rates of nonresponders were 17% (20/115) in the previous-dose group and 23% (25/109) in the low-dose group.
Tolerability was not a major issue in the study, Dr. Newcorn wrote, although adverse events were less common in the low-dose group. Headache was the most common adverse event, experienced by 21% and 16%, respectively.
“These data suggest that it is possible to maintain initial treatment gains at lower doses during continuing treatment,” he wrote. “However, they do not provide definitive evidence that the dose should be lowered during continued treatment.”
Still, he said, “The option of lowering the dose during maintenance therapy may be important for patients who respond well to initial treatment but who experience troublesome side effects.”
Dr. Newcorn is a consultant for Eli Lilly & Co., which funded the research.