Cholinergic Augmentation in Frequently Falling Subjects With Parkinson's Disease

The purpose of this study is to find out if a medication that increases levels of a brain chemical called acetylcholine will improve balance and reduce falls in patients with parkinson's disease who have the problem of very poor balance and are frequently falling or nearly falling on a daily basis. Donepezil, a drug approved for the treatment of Alzheimer's dementia, will reduce falls in subjects with Parkinson's disease and balance impairment.