The objective of this chapter is to introduce the pharmacotherapy of dementia. Elderly patients suffering from mild, moderate or severe dementia may be suffering from Alzheimer’s disease, multi-infarct dementia, dementia due to underlying disease or medical conditions like hypothyroidism, congestive cardiac failure or vitamin deficiency. Pseudodementia occur secondary to major depression. Autosomal dominant inherited disorder associated with gradual onset cognitive disorder, motor in coordination with involuntary movements and impairment of memory, starting at the age of 35–40 years. Disease gradually progresses for 15–30 years and death ensures due to complications of immobility.