Abstract
Home-based transcranial direct current stimulation (tDCS) for major depressive disorder (MDD) has progressed from early feasibility studies to an approved clinical treatment, highlighted by the US Food and Drug Administration's 2025 premarket approval of the Flow FL-100 device. This milestone shifts the field from asking whether home-based tDCS can be delivered safely and effectively to defining how it should be implemented in routine clinical practice. This review synthesizes the current evidence on treatment outcomes, adherence, and safety, with an emphasis on factors that determine successful real-world implementation. Randomized controlled trials support the efficacy of home-based tDCS when delivered using adequate cumulative dosing, structured treatment protocols, and appropriate supervision or adherence monitoring. In contrast, shorter-duration and fully unsupervised protocols have generally shown less favorable outcomes, although the independent contributions of dose, treatment duration, and supervision remain difficult to disentangle. High adherence has been reported with user-centered device design, standardized training, remote monitoring, and scalable supervision models that maintain treatment fidelity while supporting broad clinical deployment. Home-based tDCS has demonstrated an excellent safety profile when delivered using standardized equipment, structured protocols, and active monitoring, exemplified by more than 30,000 supervised home-based sessions delivered through a large academic clinical program without reported skin lesions or serious adverse events attributable to tDCS. Remaining priorities include optimizing acute and maintenance dosing strategies, identifying predictors and biomarkers of response, defining the role of paired behavioral interventions, personalizing treatment for special populations - including perinatal patients, older adults, and adolescents - and integrating home-based tDCS within interventional psychiatry care pathways. The evidence supports a transition from proof-of-concept to clinical implementation, with future research focused on optimizing delivery, personalizing treatment, and expanding access to evidence-based neuromodulation for depression.