Trends in incidence and characteristics of children, adolescents, and adults initiating immediate- or extended-release methylphenidate or atomoxetine in the Netherlands during 2001-2006.

Abstract Background: Previous Dutch studies showed increasing psychostimulant use, especially methylphenidate immediate-release (MPH-IR), between 1995 and 2003. In 2003 the extended-release (ER) formulation of MPH and in 2005 atomoxetine (ATX) were introduced in The Netherlands, which increased treatment options. Objective: The aim of this study was to describe the change in incidence of attention-deficit/hyperactivity disorder (ADHD) drugs and the prescription profiles of patients younger than 45 years starting treatment with these medicines between 2001 and 2006. Methods: Data were obtained from Dutch community pharmacies as collected by the Foundation for Pharmaceutical Statistics, covering 97% of all dispenses for prescription medicines to outpatients in The Netherlands. Results: The overall incidence of ADHD drugs use increased 6.5-fold from 2001 to 2006 in men as well as in women. The absolute incidence was highest among 6- to 11-year-old boys. The percentage of first-time MPH-IR users decreased from 98.3% in 2001 to 75.9% in 2006. Likewise, MPH-ER use increased from 0% in 2001 to 18.9% in 2006, and ATX use increased from 0% in 2001 to 3.9% in 2006. The new nonstimulant drug ATX was prescribed more often to adults if they had been previously treated with selective serotonin reuptake inhibitors (SSRIs), benzodiazepines, or antipsychotics. Youngsters