Ninety-two patients affected by chronic cerebrovasculopathy were treated with cytidine diphosphate choline (CDP-choline) 1000 mg/day i.m. or with placebo, in a double-blind study. Two cycles of therapy of 4 weeks each were performed, with an interval of 1 week. There were 46 patients in each group with chronic cerebrovascular diseases, and the two groups were comparable as far as mental deterioration was concerned. The following psychometric tests were administered: Toulouse-Piéron (attention to non-verbal stimuli), Randt Memory test (memory), Sandoz Clinical Assessment of Geriatrics (SCAG, measurement of the behavioral and emotional control). The comparison between the two groups revealed significant improvements in the CDP-choline group compared with the placebo group in some of the attention capabilities (decrease in the number of wrong answers at the Toulouse-Piéron test), of the mnemonic capabilities ('General Information' subtest of Randt Memory test) and behavioral capabilities (SCAG 'affective disturbances' score). No side-effects were detected in the CDP-choline group.