It is well known that in the brain of the patients with Alzheimer's disease there is a glutamatergic hyperstimulation leading to neuronal death. Memantine is a low affinity antagonist of NMDA glutamate receptors. The use of this drug in the early phases of the disease could provide neuroprotective effects and delay of progression. The effects of memantine should be compared to those of donepezil, which is the most prescribed anticholinesterase drug.