An Association of Intrusive, Repetitive Phrases with Lamotrigine Treatment in Bipolar II Disorder

Abstract

Bipolar disorder is frequently associated with obsessional symptoms. However, no reports have identified a pattern of obsessionality that is associated with a specific mood stabilizer treatment. A chart review was conducted on five patients with bipolar II disorder who spontaneously reported a form of obsessionality characterized by intrusive, recurrent phrases after taking lamotrigine. Development of the phrases occurred from 7-42 years after mood disorder onset and occurred only after initiation of lamotrigine treatment. The phrases improved with lamotrigine discontinuation or dose reduction and recurred with lamotrigine re-challenge or upon dose escalation. A possible mechanism for the development of the intrusive phrases involves the influence of lamotrigine on glutamatergic regulation in a bipolar II disorder population vulnerable to the expression of obsessionality. Limitations of this report include its observational nature, small number of cases reported, and confound of concomitant medication use.