Dementia is loss of cognitive ability and disturbance of mental function, due to certain process in brain. This condition often happens to elderly/aged person, but may also as a result of brain injury or other illness. There are many types of dementia, but the most common form of dementia is caused by Alzheimer's disease. Some other dementia types are vascular dementia, Parkinson's dementia, unspecified dementia, etc.
Several medicines have been developed and used as pharmacologic therapy to slow down dementia's progress.