An overview of transcranial direct current stimulation for tic symptoms in Tourette's syndrome.

INTRODUCTION: While there are many treatment options available for Tourette Syndrome, including pharmacotherapy and behavioral therapy, these treatments may lead to incomplete symptom relief or side effects. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses constant, low current delivered via electrodes attached to the scalp in order to modulate brain signals. tDCS has been explored as an alternative treatment option for tics in both pediatric and adult populations. While some studies have demonstrated that cathodal tDCS over the Supplementary Motor Area leads to improvement in tics compared to baseline as well as trends toward improvement in tics compared to sham stimulation, other studies have had mixed results or worsening of symptoms.

AREAS COVERED: Herein, the authors discuss the recent studies on tDCS for Tourette syndrome and highlight the most common side effects found. The authors also comment on the limitations these studies have and provide their expert perspectives on its prospects as a treatment option. This article is based on a PubMed literature focusing on the terms 'transcranial direct current stimulation OR tDCS' AND 'tic OR Tourette.'

EXPERT OPINION: While tDCS is a promising treatment to explore, it is premature to recommend it as a primary or adjunctive therapy outside the experimental setting. The optimal stimulation protocol, brain target, and treatment duration have yet to be elucidated; therefore, additional larger, sham-controlled, randomized studies are needed to determine the best way to incorporate tDCS into clinical practice.