Medical Definition of donepezil
: a drug taken orally in the form of its hydrochloride C24H29NO3·HCl to treat dementia associated with Alzheimer's disease
Note: Donepezil reversibly inhibits the action of acetylcholinesterase, which results in an increase in the concentration of the neurotransmitter acetylcholine. Donepezil is marketed under the trademark Aricept and when used in combination with memantine, under the trademark Namzaric.
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