Many patients have been treated with this procedure and no serious side effects have been reported to date. Very brief scalp itching may occur. Scalp irritation at the site of the electrodes can occur. On a few occasions, small, surface scalp burns have been reported.
There is little information about long-term outcome with this treatment. However, tDCS has been tested in thousands of subjects worldwide with no evidence of toxic effects to date, including studies which monitored cognitive (thinking) functions of the brain.
Brunoni et al, Brain Stimulation (2012) 5, 175–95