Original ArticleEfficacy and Safety of Donepezil in the Treatment of Executive Dysfunction in Parkinson Disease: A Pilot StudyLinazasoro, Gurutz MD; Lasa, Asier MD; Van Blercom, Nadége MDAuthor Information From the Centro de Investigación Parkinson, Policlínica Gipuzkoa, San Sebastián, Spain. Reprints: Dr. Gurutz Linazasoro, Centro Parkinson, Policlínica Gipuzkoa, Parque Tecnológico de Miramón, 20009 San Sebastián (Gipuzkoa), Spain (e-mail: firstname.lastname@example.org). Clinical Neuropharmacology: July-August 2005 - Volume 28 - Issue 4 - p 176-178 doi: 10.1097/01.wnf.0000172498.24770.54 Buy Metrics Abstract Cognitive disturbances in Parkinson's disease (PD) are dominated by troubles in executive functions which affects to a vast majority of parkinsonian patients since the onset of the disease. A common clinical observation is that parkinsonian patients, who eventually develop dementia, exhibit subtle cognitive disturbances quite earlier. The main biochemical substrate of cognitive dysfunction in PD, even of the early dysexecutive syndrome, might be a cholinergic deficiency. The aim of this pilot study was to determine the efficacy and safety of donepezil in the treatment of 10 patients with PD and dysexecutive alterations without dementia. All the items of the Clinical Global Impression were significantly improved. An improvement on both the modified Wisconsin Card Sorting Test and DIGIT Span was found. Parkinsonism remained unchanged during the study. Only 1 out of 10 patients experienced transient and mild gastrointestinal side effects. This study suggests that donepezil may be useful in the treatment of the dysexecutive syndrome associated with PD. © 2005 Lippincott Williams & Wilkins, Inc.