AbstractNon-invasive brain stimulation methods are currently being evaluated for treatment of addictive disorders. Some evidence indicates that modulating left and right prefrontal brain activity by transcranial direct current stimulation (tDCS) can reduce craving and relapse rates in tobacco addiction. Therefore, this study investigated the effects of active and sham tDCS as an add-on treatment to a standardized brief intervention for smoking cessation. This randomized, double-blind study included 36 participants (22 women and 14 men) with nicotine dependence according to ICD-10 criteria. At five visits on alternate days, participants underwent a 20-min active or sham tDCS over the left dorsolateral prefrontal cortex and subsequently participated in a 10-min brief intervention for smoking cessation. Patients were followed up after 3 months. On each treatment day and at follow-up, abstinence was assessed as the smoking status nonsmoker and craving was assessed with the German version of the Questionnaire on Smoking Urges. At each visit, the number of cigarettes smoked per day was recorded and carbon monoxide in expired air and cotinine in saliva were measured. At follow-up, a study-specific questionnaire was used to assess tobacco use. All 36 participants completed the treatment sessions, but one participant in each group was lost to follow-up. Abstinence rates were not significantly different between the groups at any of the study visits, but craving was significantly lower in the active group at tDCS session 5 compared with session 1. tDCS combined with a brief intervention may support smoking cessation, but studies need to evaluate whether longer and more intensive treatment can achieve significant, sustainable effects.