Ketamine and Lamotrigine Combination in Psychopharmacology: Systematic Review

A review of animal and human studies on combining ketamine with lamotrigine found that animal models suggested a synergistic antidepressant effect, while studies in healthy humans showed lamotrigine pretreatment reduced ketamine-induced dissociative symptoms. In a study of depressed patients, a single ketamine infusion combined with lamotrigine did not produce a stronger antidepressant effect than ketamine alone. A case series described antidepressant and anti-suicidal effects in two bipolar patients. Clinical studies in mood disorder patients did not support lamotrigine reducing ketamine-induced dissociation. The available evidence was insufficient to answer the review's questions, but pointed to future research directions, including controlled studies in bipolar patients with multiple ketamine infusions.

Study at a glance

Abstract

BACKGROUND AND OBJECTIVES: Ketamine is a rapid-acting antidepressant with proven efficacy as an add-on agent in unipolar and bipolar treatment-resistant depression. Although many studies have been published, there is still not enough data on the effect of ketamine in combination with other medications. Particularly interesting is the combination of ketamine and lamotrigine, and its potential role in bipolar depression. The aim of this review was to identify animal and human studies in which ketamine and lamotrigine were used together in order to find out if there is scientific ground for combining ketamine and lamotrigine in the treatment of mood disorders. Directions for future studies are presented. MATERIALS AND METHODS: PubMed and Web of Science were searched. Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA 2020 methodology was applied. RESULTS: Seventeen studies were included for review. Animal studies using models of depression suggested a synergistic effect of ketamine and lamotrigine in combination. Studies on healthy humans showed a reduction in ketamine-induced dissociative symptoms with lamotrigine pretreatment. In a study on patients with depression, ketamine and lamotrigine did not have a stronger antidepressant effect than ketamine alone, but in this study only one ketamine infusion was administered. One case series described the antidepressant and anti-suicidal effect of the combination in two bipolar patients. Available clinical studies on patients with mood disorders did not support the hypothesis that lamotrigine reduces ketamine-induced dissociative symptoms. CONCLUSIONS: The results of the analyzed studies were not sufficient to answer any of the stated questions; however, they allowed us to delineate future research directions. The identified animal studies suggested a possible synergistic antidepressant effect of ketamine and lamotrigine. The available clinical studies were not conclusive. No controlled studies on large groups of bipolar patients with multiple ketamine infusions combined with lamotrigine treatment have been published so far. There is some evidence for the reduction of ketamine's side effects by lamotrigine, and there are reports suggesting that lamotrigine can reduce ketamine craving. More studies with follow-up are needed in order to investigate the ketamine-lamotrigine combination in bipolar patients.