 The purposes of this pilot study are to determine: 1 the safety and tolerability a cholinesterase inhibitor medication in aged hip and long bone fracture patients, 2 To obtain estimates of subject accrual and preliminary estimates of effect size on the development of new delirium symptoms to allow for planning of a larger, definitive trial, 3 To better understand the underlying causes of delirium by examining whether a measure of blood anticholinergic activity relates to the incidence and persistence of delirium symptoms, and 4 To explore the interaction between anticholinergic activity, donepezil therapy, and delirium symptoms. 