Lewy body dementia became today a distinct nosological entity, considered by many authors the second cause of degenerative dementia, after Alzheimer's disease. Its neuropathology is caracterized by the presence of Lewy bodies both in cortical and subcortical areas of the brain. The main clinical manifestations are: progressive cognitive impairment, recurrent visual hallucinations, fluctuating cognitive status and parkinsonian signs. There is greater sensitivity to side effects of neuroleptic drugs and the response to cholinesterase inhibitors is generally good.