Memantine augmentation of escitalopram in treatment of executive function among patients with obsessive-compulsive disorder (OCD): a double-blind placebo-controlled randomized clinical trial.

Background: Obsessive-Compulsive Disorder (OCD) involves persistent, intrusive thoughts and repetitive behaviors. While SSRIs like escitalopram are common treatments, some patients do not respond adequately. This study aims to assess memantine's effectiveness as an adjunct therapy to enhance executive function in OCD patients.

Methods: This study was a 16-week, randomized, double-blind, placebo-controlled clinical trial to evaluate if adding memantine to escitalopram helps treat OCD. A total of 60 participants were recruited from Namazi Hospital and Ibn Sina Polyclinic in Shiraz, Iran. Participants were randomly divided into two groups: the control group received escitalopram plus placebo, and the intervention group received escitalopram plus memantine. The main outcome, the severity of OCD symptoms, was measured using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), and executive function was assessed using the Barkley Deficits in Executive Functioning Scale (BDEFS). Safety was checked weekly using the Drug Adverse Event Questionnaire. Data were analyzed using SPSS, with a significance level set at p < 0.05.

Results: All sixty participants completed the 16 weeks of the study. Thirty participants per group (Placebo, Memantine) showed no significant differences in age, gender, or education (P > 0.05) at baseline. Both groups showed significant reductions in Y-BOCS scores (P < 0.001), with the Placebo group decreasing from 32.83 (SD = 4.04) to 5.30 (SD = 3.18) and the Memantine group from 31.60 (SD = 2.62) to 5.20 (SD = 2.62) without difference between groups (P = 0.12). Notebale Improvements in executive function were observed, particularly in time management, where Memantine outperformed Placebo (P = 0.03). Other domains showed no significant differences. Adverse events were minimal; gastrointestinal symptoms were rare, with Memantine showing a higher incidence but not statistically significant.

Conclusion: The study found that while both treatment regimens significantly alleviated OCD symptoms, memantine did not provide notable advantages over escitalopram alone, except in time management. Further research is needed to assess long-term effects and mechanisms of this combination therapy.

Trial registration: IRCT20211118053093N5, 25/06/2025.