Dementia and Delirium are difficult conditions both to differentiate and to experience. Dementia is a condition of progressive decline in intellectual function and other cognitive abilities that results in a decline in an individual's performance in his or her daily activities. Unlike dementia, delirium, also known as acute confusional state, is an acute medical condition that causes confusion and other disruptions in a person's thinking and behavior, including attention, activity level, and perception. It is very important to distinguish between the two conditions because delirium can be found in a person who already suffers from dementia. A study conducted by Fick and Mion (2008) indicated that approximately 22% of adults with dementia develop delirium. Dementia and delirium can cause impaired functioning, memory loss, poor judgment, and speech problems; however, there are many differences between the two. Although delirium and dementia can manifest with similar symptoms, they are two different conditions. This is because an individual can suffer from both delirium and dementia and therefore it is very important to distinguish between the two. Furthermore, delirium is reversible while dementia is a permanent condition. Therefore, differentiating the two will help in the rapid treatment of delirium. The causes of the two conditions are similar in one way or another and at the same time vary. Delirium is caused by acute illness or drug toxicity, while dementia is caused by anatomical changes in the brain that are generally irreversible. Dementia is a condition caused by Alzheimer's disease, Lewy body dementia, vascular dementia, promptotemporal dementia, and other related diseases. It can also be caused by emotional illnesses, metabolic disorders, trauma… middle of the paper… medical conditions. The two conditions coexist and this complicates the differential diagnosis in patients with cognitive impairment. Patients with cognitive dysfunction should identify potential causes of their deterioration because; Dementia and delirium have similar symptoms and therefore require distinct treatment strategies. Dementia and delirium are characterized by cognitive decline in which brain function changes. Both influence an individual's attention, thinking and personality. Works Cited Whaley, L. & Breitner, J. (2002) Dementia. London: Health Press.Fick, D.M. & Mion, L.C. (2008). Delirium superimposed on dementia. American Journal of Nursing, 108(1), 52-60. Ajilore, O. A., & Kumar, A. (2004). Delirium and dementia. FOCUS, 2, 210-220.Arnold, E. (2004). Distinguish the 3 Ds: delirium, dementia, depression. Nursing care, 34 (6), 36–42.