Safety and Tolerability of Lisdexamfetamine: A Retrospective Cohort Study

BACKGROUND: Attention-deficit hyperactivity disorder (ADHD) is a common neurobehavioural disorder in children. Pharmacotherapy plays a main role in multimodal treatment, albeit adverse effects are a concern. Lisdexamfetamine is a newer pharmacological option and post-marketing studies on adverse events are limited.

OBJECTIVE: The aim of this study was to investigate the treatment-emergent adverse events (TEAEs) in patients receiving lisdexamfetamine in a clinical setting.

METHODS: We performed a retrospective cohort study at the Department of Child and Adolescent Psychiatry of Glostrup Hospital in Copenhagen, Denmark. We included all consecutive patients >6 years old, with an ICD-10 diagnosis of ADHD who were initiated on lisdexamfetamine between May 2013 and July 2014. TEAEs were assessed by a clinician and chart audit.

RESULTS: Forty-three patients (91 % male) with a median age of 11 (range 8-15) years were included and received lisdexamfetamine for a median of 188 days (range 3-433). In total, 23.3 % of the patients discontinued treatment due to a TEAE. 88 % of the patients experienced at least one TEAE and the time to first TEAE ≤4 weeks in 83.8 % of the patients. A new TEAE was experienced by 39.5 % of the patients compared with the TEAEs that patients had experienced when taking previous ADHD medication. The most common TEAEs (≥5 %) were decreased appetite, difficulty falling asleep, tics, stomach ache and weight loss. A subjectively assessed good or good but time-limited (during the day only) effect was observed in 62.7 %.

CONCLUSION: Lisdexamfetamine treatment in this small group of patients who had received previous stimulant medication for ADHD was well tolerated and the TEAEs were consistent with findings in previous trials, although more than one third of the patients experienced TEAEs not observed with previously taken ADHD medication. Both the number of patients experiencing TEAEs and the rates of discontinuation due to TEAEs were higher than previously reported.