Donepezil hydrochloride is a medication used for the treatment of Alzheimers disease, a progressive neurological disorder that affects memory, thinking, and behavior. It is classified as a cholinesterase inhibitor.Donepezil hydrochloride works by increasing the levels of acetylcholine, a neurotransmitter involved in memory and cognitive processes, in the brain. By inhibiting the enzyme acetylcholinesterase, which breaks down acetylcholine, donepezil helps to enhance cholinergic neurotransmission and improve cognitive function in individuals with Alzheimer's disease.