Aricept 5 mg tablet contains Donepezil 5 mg which is used in the treatment of Alzheimer's disease and dementia in Parkinson's disease. It should be used in patients with moderate to severe Alzheimer's disease. Memory loss in Alzheimer’s disease occurs due to disturbances of signal transmission in the brain. Aricept 5 mg Tablet is a cholinesterase inhibitor. It works by increasing the levels of a chemical messenger (acetylcholine) involved in transmission of nerve signals. This improves memory and thinking.