Lamotrigine use and potential for adverse cardiac effects: A retrospective evaluation in a Veteran population.

Objective: To identify the impact of lamotrigine (LTG) on cardiac rhythm and conduction abnormalities for Veterans, an especially vulnerable population.

Background: In October 2020 the US Food and Drug Administration (FDA) added a new warning to the label of lamotrigine (Lamictal™) regarding its potential to cause cardiac rhythm and conduction abnormalities [1]. This warning came following in vitro data which suggested Class IB antiarrhythmic effects occurring at clinically achievable concentrations of lamotrigine [2].