[Comment] US FDA premarket approval of tDCS depression treatment is not yet scientifically justified

Abstract

With major depressive disorder (MDD) being a common psychiatric condition in the world's population, easily accessible treatments with high efficacy and low health risks in early phases of the disorder can mitigate symptom progression and reduce long-term negative effects. Transcranial direct current stimulation (tDCS) has shown promise in alleviating depressive symptoms, and consensus guidelines have classified tDCS as definitely effective (level A) for treating depression.1 On Dec 8, 2025, a tDCS device designed for at-home application, as monotherapy or adjunct treatment of moderate to severe non-treatment resistant MDD, received premarket approval by the US Food and Drug Administration (FDA).