Twenty-two patients suffering from mild to moderate dementia of vascular origin were treated with vinpocetine, 30 mg/day during 16 weeks, in an open pilot study. Response to treatment was assessed with the Gottfries-BrÅne-Steen geriatric rating scale and psychometric tests. Effects on concentrations of neurotransmitters in the cerebrospinal fluid (CSF) and on the blood-brain barrier function were also studied. According to the ratings and tests, the only noticeable improvement was reduced fear/panic. This improvement may very well be attributable to increased care of the patients during the study. The drug did not influence the monoamine metabolites in the CSF or the blood-brain barrier function. On the basis of these results we conclude that vinpocetine has no effect on patients suffering from mild to moderate dementia of vascular origin.