Lamotrigine-Induced Blood Dyscrasias in Association with Rash

Abstract

INTRODUCTION Lamotrigine is used to treat a number of disease states, including bipolar disorder. It is generally well tolerated, with dizziness, insomnia, and skin rashes being the adverse effects most often reported. The prevalence of rash among patients receiving lamotrigine is approximately 10%, but serious rashes associated with hospital admission are rare (0.3%).1 Increased frequency of dermatologic events has been associated with more rapid initial titration of lamotrigine and with concomitant use of valproic acid, a known inhibitor of lamotrigine metabolism.1 Blood dyscrasias associated with lamotrigine have been reported, but the numbers are too few to estimate the incidence.1 We report here a case of lamotrigine-induced leukopenia (leukocyte count less than 4.0 x 109/L) and neutropenia (neutrophil count less than 1.5 x 109/L) associated with rash. This case illustrates the potential morbidity associated with lamotrigineinduced blood dyscrasias.