sundowning

American  

[suhn-dou-ning] / ˈsʌnˌdaʊ nɪŋ /

noun

1. Psychiatry. a state of confusion, disorientation, or anxiety seen late in the day or at night, especially in dementia patients, likely as a result of strange surroundings, drug effects, decreased sensory input, or reduction of oxygen supply to the brain.

   Two randomized controlled trials of the new drug have found a significant improvement in sundowning and other agitated behavior.

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Etymology

Origin of sundowning

First recorded in 1870–75, for an earlier sense; sundown ( def. ) + -ing ¹ ( def. )

Example Sentences

See Examples For:

sundowning

In later stages, patients often experience "sundowning," a period of increased confusion and agitation that tends to occur later in the day.

From Science Daily ● Nov. 3, 2025

Hard as it may be to believe, this lunchtime perfomance was less of a sundowning moment than his speech in Virginia on Saturday night.

From Salon ● Mar. 6, 2024

Goldman goes through a sundowning stage in the afternoon, a period of the day where typically those with mid- to late-stage dementia can have increased irritability or changes in behavior.

From Washington Post ● Jul. 2, 2021

They believe it might help doctors chart the development of a disease like Alzheimer's, by measuring, for example, the onset of sundowning syndrome.

From BBC ● May 22, 2021

The latter, called "sundowning," occurs in people with dementia, although the cause is unclear.

From Newsweek ● Feb. 2, 2012