"Sundowning", or sundown syndrome, is increased confusion, agitation or disorientation in the late afternoon, evening, and night-time, which may be seen in patients with delirium, and sometimes in dementia. In dementia, there may be complete reversal of sleep schedule with daytime somnolence and nocturnal wakefulness. Although this syndrome may relate to worsening of visual cues with increasing darkness, it may also occur in well-lit environments. A disorder of circadian rhythms is a possible physiological correlate of "sundowning": EEG recordings in delirious patients may suggest this. Suggested management for dementia patients with sundowning includes use of structured activities at the relevant times, and increased staffing or availability of family members. Sedative medications are probably best avoided.



Evans LK. Sundown syndrome in institutionalized elderly. Journal ofthe American Geriatrics Society 1987; 35: 101-108
Volicer L, Harper DG, Manning BC, Goldstein R, Satlin A. Sundowning and circadian rhythms in Alzheimer’s disease. AmericanJournal of Psychiatry 2001; 158: 704-711


Cross References

Delirium; Dementia