Aricept (also known as donepezil) is a cholinesterase inhibitor used in the treatment of Alzheimer's disease. The dementia of Alzheimer's is partially related to a deficiency in a brain chemical called acetylcholine (ACh). Cholinesterases are enzymes that break down ACh. By inhibiting the enzyme, Aricept increases the amount of ACh available. The amount of benefit that Aricept and the other cholinesterase inhibitors provide to patients with Alzheimer's is open to some debate at the moment. Although many studies show that patients can have better scores on certain dementia tests while taking these drugs, few studies actually show an improvement in the quality of life in people with Alzheimer's.

Recently the watchdog arm of the National Health Service in the United Kingdom recommended that Aricept no longer be covered because of a lack of conclusive evidence to support a meaningful treatment effect in people with Alzheimer's.

A recent study looked at the effects of Aricept in people with mild cognitive impairment. At the end of 24 weeks, people taking Aricept were no better off than those taking a placebo (a look-alike but inactive sugar pill). This study was not conclusive, and more studies are needed.

I am not aware of any evidence that Aricept and similar drugs offer any advantage to older adults of any age unless the diagnosis of Alzheimer's has been made. Aricept and similar drugs cause side effects. About 1 of every 10 people taking the drug will need to stop because of side effects. There is no evidence that Aricept would reduce the risk of Alzheimer's or change its onset, and there are significant side effects seen with its use.