Adverse Events in Medication Treatment-Naïve Children with Attention-Deficit/Hyperactivity Disorder: Results from a Small, Controlled Trial of Lisdexamfetamine Dimesylate

Abstract

OBJECTIVE: To evaluate the type, frequency, duration, and severity of treatment emergent adverse events (TEAEs) of the prodrug lisdexamfetamine dimesylate (LDX) in children with and without previous exposure to stimulant medication in the treatment of attention-deficit/hyperactivity disorder (ADHD). METHODS: This single-blind, modified laboratory school study used open-label, dose optimization of children aged 6-12 years. LDX, initiated at 30 mg, was dose titrated in 20 mg increments to a possible 70 mg over 4-5 weeks. Safety was assessed using adverse effects and LDX levels. RESULTS: Twenty-eight subjects enrolled in the study, with 27 safety protocol completers (n=14 previous stimulant exposure; n=13 stimulant naïve). The stimulant-naïve group reported more trouble sleeping, stomach pain, and hyperfocus, but only previous-exposure subjects experienced dizziness. Previous-exposure subjects showed trends of more decreased appetite, less talkativeness, and less lip sucking. There were no differences in the mean duration of TEAEs. The epidemiological method of percent person-weeks applied to ADHD treatment offers a novel approach to interpreting the pattern of TEAEs. CONCLUSION: LDX reduced the core symptoms of ADHD with more severe adverse events in stimulant-naïve than previous-exposure subjects. Future controlled studies with larger samples should address the impact of previous stimulant exposure on other ADHD treatments.