Psychology Wiki

Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |

Clinical: Approaches · Group therapy · Techniques · Types of problem · Areas of specialism · Taxonomies · Therapeutic issues · Modes of delivery · Model translation project · Personal experiences ·

In medicine, sundowning, also known as sundown syndrome, is a syndrome involving the occurrence or increase of one or more abnormal behaviors in a circadian rhythm.[1] Sundowning typically occurs during the late afternoon, evening, and night, hence the name. It occurs in persons with certain forms of dementia and psychosis, such as seen in Alzheimer's disease. Although not widely surveyed, sundowning is estimated to occur in 45% of persons diagnosed with Alzheimer's disease.[2] A person who is sundowning may become abnormally demanding, suspicious, upset or disoriented, and see or hear things that are not there. After wandering, sundowning is the second most common type of disruptive behavior in institutionalized persons with dementia.[3] Sundowning often co-occurs with wandering, and the combination of these two syndromes is an important contributing factor to an emergency situation: elopement at night. The cause of sundowning is unknown, but may be related to disturbed circadian rhythm.


Although the cause of sundowning is unknown, proposed causes include sensory deprivation from lower light conditions in the evening, and fatigue.[How to reference and link to summary or text] Alzheimer's disease alters the normal daily cycle of changes in body temperature, and sundowning appears to be related to delay of those changes that normally occur in the evening.[1][4] Contributing factors may include medications that can cause agitation or confusion,[5] and sleep disorders.[How to reference and link to summary or text]


In persons with early Alzheimer's disease, the presence of sundowning has been associated with faster decline in cognitive functions.[6]


Behavioural disturbance is often treated with antipsychotic medication such as haloperidol, risperidone, or olanzapine. However, these have significant side effects.[How to reference and link to summary or text]

External links


  1. 1.0 1.1 Volicer L, Harper DG, Manning BC, Goldstein R, Satlin A (May 2001). Sundowning and circadian rhythms in Alzheimer's disease. Am J Psychiatry 158 (5): 704–11.
  2. Scarmeas N, Brandt J, Blacker D, et al (December 2007). Disruptive behavior as a predictor in Alzheimer disease. Arch. Neurol. 64 (12): 1755–61.
  3. U.S. Congress, Office of Technology Assessment (1992). Special care units for people with Alzheimer's and other dementias: Consumer education, research, regulatory, and reimbursement issues., Government Printing Office.
  4. Satlin A, Volicer L, Stopa EG, Harper D (1995). Circadian locomotor activity and core-body temperature rhythms in Alzheimer's disease. Neurobiol. Aging 16 (5): 765–71.
  5. Alzheimer’s Disease: Questions and Answers. Cleveland Clinic Regional Hospitals
  6. Scarmeas N, Brandt J, Blacker D, et al (December 2007). Disruptive behavior as a predictor in Alzheimer disease. Arch. Neurol. 64 (12): 1755–61.

Template:Mental and behavioral disorders

This page uses Creative Commons Licensed content from Wikipedia (view authors).