In November 1996, donepezil hydrochloride (Aricept; Pfizer) was approved by the Food and Drug Administration (FDA) as a symptomatic therapy for mild and moderate Alzheimer's disease (AD). Although it was preceded to the United States market by tacrine (Congex; Parke-Davis) by more than 3 years, donepezil's ease of use and favorable safety profile, coupled with clinically meaningful efficacy, represent a major step forward in dementia treatment (1-6). Donepezil hydrochloride, a piperdine-based second-generation acteylcholinesterase inhibitor, is now being marketed for oral treatment of cognitive symptoms in patients with mild to moderate dementia due to Alzheimer's disease (7,8). It is the only drug licensed in Britain for the treatment of Alzheimer's disease, although tacrine, another acetylcholinestrease inhibitor, is available in the United States and France (9,10). Donepezil is the first drug approved by the Health Protection Branch of Health Canada for the symptomatic treatment of early to intermediate stages of AD.