Lamotrigine-Associated Toxic Epidermal Necrolysis in a Southeast Asian Female: A Case Report Highlighting Sex and Ancestry-Related Susceptibility.

Background: Stevens-Johnson syndrome (SJS) is a known, but rare adverse effect of Lamotrigine, occurring in less than 0.1% of the population. Rapid dose titrations of Lamotrigine, an antiepileptic used off-label for the treatment of bipolar disorder, have been shown to increase the risk of SJS, and in even rarer cases, progression to toxic epidermal necrolysis (TEN), which currently has too few cases to report an estimated incidence. Data suggest that additional factors, including female sex and certain HLA alleles associated with East and Southeast Asian ancestries, may be associated with increased risk of Lamotrigine-induced SJS/TEN. Case presentation: This case presents a 26-year-old Southeast Asian female with bipolar I disorder who developed SJS shortly after her Lamotrigine dose was titrated appropriately from 50 milligrams (mg) to 100 mg daily, which rapidly progressed to TEN. The patient received treatment, including steroids, intravenous (IV) immunoglobulin, and surgical debridement, and was discharged home in stable condition after 8 days. Conclusion: This case prompts consideration of sex and ancestry when identifying high-risk populations taking Lamotrigine. Continued research into sex- and ancestry-based pharmacogenomics may reduce the incidence of these life-threatening reactions.