Three major lines of drugs have been developed or are under development for the treatment of Alzheimer Disease (AD): cholinergic drugs (mainly cholinesterase inhibitors), anti-beta-amyloid drugs, estrogens and anti-inflammatories. Cholinesterase inhibitors are the only drugs presently approved in USA and Europe for the indication of AD. Cholinesterase inhibitors tested in clinical trials in Europe, USA and Japan include less than ten drugs, however most of these compounds have advanced to clinical trials III. Based on results related to a population of over 8,000 patients we conclude that several of these compounds have shown significant clinical efficacy and safety in the treatment of Alzheimer disease. There are, however, differences with regard to side effects. The major clinical effect is stabilization of cognitive function during a six- to 12-months period with a parallel improvement of behavioral symptoms. Long-term effect of cholinesterase inhibitors extending to a two year-period has been reported. Future applications of these drugs are treatment of other types dementias such as Lewy body dementia, vascular dementia and Down Syndrome dementia. Combination of cholinesterase inhibitors with estrogens, anti-oxidants and anti-inflammatories may represent a further improvement of the therapy. From the economical point of view, treatment with cholinesterase inhibitors is not cost neutral.