Lamotrigine-induced obsessive-compulsive disorder in patients with bipolar disorder

Introduction Lamotrigine is a commonly used drug in the treatment of bipolar disorder. Although there are reports of its effectiveness in the management of bipolar disorder and comorbid obsessive-compulsive disorder (OCD), lamotrigine has also been associated with obsessionality in patients with bipolar disorder. Methods Charts of 8 patients with bipolar disorder who had de novo onset of obsessions and compulsions after the use of lamotrigine were reviewed. The Naranjo scale was used to assess the likelihood of patients developing OCD due to lamotrigine use. Results Two to 8 months after the initiation of lamotrigine, patients with no such prior history developed obsessions and compulsions meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnostic criteria for medication-induced OCD. In all except 1 patient, the symptoms resolved within a month of lamotrigine discontinuation. Conclusions Some patients with bipolar disorder may develop OCD after initiation of lamotrigine. Due to the inherent limitations of a case series, the findings should be interpreted with caution.