Introduction and objective:
Obsessive-compulsive disorder (OCD) is a chronic, often treatment-resistant condition involving dysfunction in the cortico-striato-thalamo-cortical (CSTC) circuit and neurotransmitter imbalances. Standard treatments, including SSRIs and cognitive-behavioral therapy (CBT), are insufficient for a substantial proportion of patients. Transcranial direct current stimulation (tDCS), a non-invasive, cost-effective neuromodulation technique, has emerged as a potential therapeutic option. The aim of the review is to critically evaluate current evidence on the efficacy, safety, and clinical utility of tDCS in OCD treatment, emphasizing optimal stimulation targets, parameters, therapeutic outcomes, and areas requiring further investigation

Review methods:
A literature review was conducted using PubMed and Google Scholar databases (2020–2025), based on key words: ‘transcranial direct current stimulation’, ‘obsessive-compulsive disorder’, ‘brain stimulation’, ‘efficacy’, and ‘neuromodulation’.

Brief description of the state of knowledge:
Evidence suggests that stimulation of the pre-SMA, dlPFC, OFC, and ACC can significantly reduce OCD symptom severity. Meta-analyses report moderate short-term efficacy with a favourable safety profile. However, patient responses vary widely, and current studies use heterogeneous protocols with inconsistent outcome measures.

Summary:
tDCS demonstrates promising short-term benefits and good tolerability in treating OCD, particularly when targeting cortico-striatal network hubs. However, lack of standardized protocols and limited long-term data constrain its clinical adoption. High-quality randomized trials with uniform methodologies are essential to validate its role as a reliable adjunctive treatment in OCD management.