Donepezil is a drug usually used to treat Alzheimer's disease and other forms of dementia. It is sold under various brand names including Aricept.
It is in a class of medications called cholinesterase inhibitors which work by increasing the amount of acetylcholine (a neurotransmitter ) in the brain.
This helps to improve mental function (such as memory, attention, social interaction, reasoning and language abilities, and ability to perform activities of daily living).
Some people believe that donepezil can also be used to treat some of the problems facing people with autism.