The influence of buflomedil on brain circulation was investigated in an open, preliminary trial in 12 patients with dementia caused by multi-cerebral infarcts. Patients were given 150 mg buflomedil 3-times daily for a period of 6 months. Assessments carried out before treatment included regional cerebral blood flow measurements, using a 133Xenon technique, as well as psychometric tests (Weschler and Benton), psychiatric and neurological evaluations, and routine clinical and laboratory (blood and urine) examinations. The tests and investigations were repeated on Days 90 and 180 of treatment. The results showed that mean regional cerebral blood flow increased by 15% to 22% and 16% to 24% in the right and left hemispheres, respectively, by the end of the trial, and marked improvements were noted in psychiatric symptoms and scores in the psychometric tests. A controlled, double-blind study is being planned to validate these preliminary findings.