BACKGROUND: Neuro-psychiatric (NP) disturbances are highly prevalent in patients with Parkinson's disease (PD) and contribute to worsen quality of life. Deep brain stimulation of the subthalamic nucleus (STN-DBS) is commonly utilized as surgical treatment for advanced PD with motor complications. The effectiveness of the procedure on motor symptoms is well established whereas the effects of STN-DBS on NP symptoms are less clear. The aim of our study was to analyze the postoperative pharmacological therapy for NP symptoms in a group of STN-DBS treated PD patients. Such therapy provides indirect information about the evolution of underlying NP disturbances during the follow-up in this group of PD patients. METHODS: NP therapy (benzodiazepines, antidepressants, antipsychotics) was assessed in 48 consecutive PD patients treated by STN-DBS, preoperatively and postoperatively after 4months, 1year and 3years. Motor symptoms were evaluated by the Unified PD Rating Scale (UPDRS) and levodopa equivalence daily dose (LEDD) was calculated. Cognitive, mood and anxiety assessments were performed with appropriate rating scales. RESULTS: The number of patients treated with antidepressant drugs gradually increased during the follow-up. The use of antipsychotic drugs was stable until 1year, with a subsequent increase at 3years. Benzodiazepines were given to fewer patients immediately after surgery. CONCLUSIONS: Pharmacological treatment supplies further information about NP symptoms in the follow-up of PD patients undergoing STN stimulation.