Donepezil hydrochloride for Dementia Related to Alzheimer's Disease...

We know that, ARICEPT® [donepezil hydrochloride, see structure  (source-chemSpider) ] is a reversible inhibitor of the enzyme acetylcholinesterase, known chemically as (±)-2,3-dihydro-5,6-dimethoxy-2 -[[1-(phenylmethyl)-4-piperidinyl]- methyl]-1H-inden-1-one hydrochloride. Donepezil hydrochloride is commonly referred to in the pharmacological literature as E2020.

Acetylcholinesterase is the target of many Alzheimer's Dementia drugs , nerve gases, particularly the organophosphates (e.g. Sarin) and insecticides (e.g. carbaryl). These agents — known as cholinesterase inhibitors — block the function of acetylcholinesterase and thus cause excessive acetylcholine to accumulate in the synaptic cleft. The excess acetylcholine causes neuromuscular paralysis (i.e. interminable muscle contractions) throughout the entire body, leading to death by asphyxiation.

The U.S. Food and Drug Administration approved the first generic versions of Aricept (donepezil hydrochloride) orally disintegrating tablets on Dec. 11. Donepezil hydrochloride is indicated for the treatment of dementia related to Alzheimer's disease. Orally disintegrating tablets dissolve on the tongue, without having to be swallowed whole. This may make it easier to take the medication for older or disabled patients who have difficulty swallowing.

Alzheimer's disease :

Alzheimer's disease is an irreversible, progressive brain disease that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks of daily living. In most people with Alzheimer's disease, symptoms first appear after age 60. Alzheimer's disease is the most common cause of dementia among older people, but it is not a normal part of aging...

Ref : http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm194173.htm