Definition of Sundowning

Sundowning: also known as Sundown Syndrome, a term used to refer to behavioral changes that often occur in the late afternoon or evening in people with Alzheimer's disease and similar conditions. The behavioral changes make take the form of aggression, agitation, delusions, hallucinations, paranoia, increased disorientation, or wandering and pacing about. Experts are not sure why these changes occur at this time of day; possible explanations include hormonal factors, reduced vision due to lower light levels, tiredness, boredom and the absence of planned activities, or stress and anxiety of the caregiver that is communicated to the patient.


Last Editorial Review: 6/14/2012

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