Below are some of the details of Donepezil(generic)
 

Donepezil (also misspelled donezepil), marketed under the trade name Aricept by its developer Eisai and partner Pfizer, is a centrally acting reversible acetylcholinesterase inhibitor.[1] Its main therapeutic use is in the treatment of Alzheimer's disease where it is used to increase cortical acetylcholine. Its binding to the acetylcholinesterase can be seen at Proteopedia 1eve. It has an oral bioavailability of 100% and easily crosses the blood-brain barrier. Because it has a half life of about 70 hours, it can be taken once a day. Initial dose is 5mg per day, which can be increased to 10mg per day after an adjustment period of at least 4 weeks.