Background and objective: Atomoxetine is a potent central norepinephrine uptake inhibitor, currently marketed for treatment of attention-deficit/hyperactivity disorder (ADHD). With the understanding that noradrenergic agents could be useful in assisting obese individuals to lose weight, we conducted this preliminary study to evaluate short-term efficacy and safety of atomoxetine in obese adults.
Design: At 12-week randomised, double-blind, placebo-controlled trial, conducted at Duke University Medical Centre, USA, from May 2004 to December 2004.
Participants: A total of 30 obese women (mean (s.e.) body mass index of 36.1 (0.6) kg/m2).
Interventions: Participants were randomly assigned to receive atomoxetine (n=15) or placebo (n=15). All participants were advised to follow a balanced hypocaloric diet (500 kcal/day deficit). Atomoxetine therapy was started at 25 mg/day orally, with gradual increase to 100 mg/day over 1 week. Placebo dosing was identical.
Measurements: Body weight in kilograms was the primary outcome measure. Other measurements included waist circumference, blood pressure and heart rate, fasting plasma glucose and lipids, and depressive symptoms.
Results: Last-observation-carried-forward analysis of the available data for participants who had completed at least one post-randomisation assessment, demonstrated that the atomoxetine group (n=12) lost more body weight over the 12-week period than the placebo (n=14) group (mean (s.e.) -3.6 (1.0) kg (-3.7% loss) vs 0.1 (0.4) kg (0.2% gain); F (4,96)=11.9; P<0.0001). Three participants in the atomoxetine group and none in the placebo group lost >or=5% weight. Side effects were minimal.
Conclusion: Atomoxetine demonstrated modest short-term weight loss efficacy relative to placebo in this preliminary study of obese women.