Sundowning most commonly appears during the middle stages of dementia, though it can start earlier and often continues into the later stages. It is not tied to one specific stage. The pattern of late-day confusion, agitation, and restlessness tends to emerge as cognitive decline progresses and worsen over time, peaking in the moderate-to-severe range before sometimes fading in very late-stage dementia when overall activity levels drop significantly.
When Sundowning Typically Appears
Sundowning is not a disease on its own. It’s a cluster of behavioral symptoms, including confusion, anxiety, agitation, wandering, and irritability, that start or intensify in the late afternoon and evening hours. In studies of dementia patients, roughly 20 to 25% experience sundowning at some point during their illness, with irritability, agitation, and anxiety being the most frequently reported symptoms.
Most people first notice sundowning behaviors during stage 4 or 5 on the seven-stage Global Deterioration Scale, which corresponds to moderate dementia. At this point, a person is already having trouble with complex daily tasks and may need help with things like managing finances or planning meals. The brain changes driving sundowning have been building for some time, but it’s during this middle phase that the symptoms become obvious enough for caregivers to recognize a pattern tied to the time of day.
Sundowning frequently intensifies through stage 6 (moderately severe dementia), when a person needs substantial help with dressing, bathing, and toileting. In very late-stage dementia (stage 7), when mobility and verbal communication are severely limited, sundowning episodes may decrease simply because the person no longer has the physical capacity for pacing, wandering, or vocal outbursts.
Why It Happens in the Afternoon and Evening
The brain has an internal clock, a small cluster of nerve cells in the hypothalamus that keeps your sleep-wake cycle on a roughly 24-hour schedule. In Alzheimer’s and other dementias, this clock gets physically damaged. Researchers have documented significant nerve cell loss and a buildup of tangled proteins in this region of the brain, along with an increase in support cells trying to compensate for the damage. The result is a biological clock that can no longer reliably distinguish day from night.
Melatonin, the hormone your brain releases in response to darkness to signal that it’s time to sleep, also declines with normal aging. In people with Alzheimer’s, melatonin levels drop even further. With a damaged internal clock producing less of the hormone that regulates sleep timing, the brain struggles to manage the transition from afternoon to evening. This is the window when sundowning strikes.
Fatigue plays a compounding role. By late afternoon, a person with dementia has spent an entire day trying to process a world that is increasingly confusing. That accumulated mental exhaustion, combined with fading daylight and a malfunctioning internal clock, creates the conditions for a sundowning episode.
What Sundowning Looks Like
The behaviors vary from person to person and can shift over time. Common signs include pacing, rocking, wandering, crying, yelling, and shadowing (following a caregiver from room to room). Some people become verbally or physically aggressive. Emotionally, the person may feel fearful, paranoid, deeply sad, or intensely restless without being able to explain why. Confusion, delusions, and hallucinations can also occur during episodes.
While the term “sundowning” implies an evening phenomenon, the timing isn’t always predictable. Some people experience their worst episodes closer to midafternoon. Others have morning episodes instead. The hallmark is a recurring pattern of worsening behavior tied to a consistent time of day, not necessarily sunset itself.
Common Triggers
Certain conditions make sundowning episodes more likely or more severe. Too much noise, too many people in the room, or an unfamiliar environment can all push a person past their threshold. Being overtired is one of the strongest triggers, which is why long afternoon naps can backfire: they disrupt nighttime sleep and leave the person in a cycle of fatigue and restlessness.
Physical discomfort matters too. Hunger, thirst, pain, a urinary tract infection, or constipation can all amplify agitation in someone who may not be able to articulate what’s wrong. Caffeine or alcohol consumed later in the day can also worsen symptoms by interfering with sleep regulation.
Strategies That Help Reduce Episodes
Sundowning can’t be cured, but it can often be made less frequent and less intense with environmental and routine adjustments. The National Institute on Aging recommends building daily sunlight exposure into the routine, either by going outside or sitting near a window. Light exposure during the day helps reinforce whatever remains of the brain’s circadian signaling, and it’s one of the simplest interventions available.
Keeping a predictable daily schedule reduces confusion. Activities and outings work best in the morning and early afternoon, with the later hours reserved for quiet, low-stimulation time. Discourage long naps or dozing after mid-afternoon. Cut off caffeine and alcohol well before evening. Keep the home well-lit as natural light fades, since dimming rooms can contribute to disorientation and anxiety.
When an episode is already underway, the goal shifts to de-escalation. Speak in a calm, simple tone. Don’t argue with or try to correct the person’s confused statements. Reduce noise by turning off the television or moving to a quieter room. Gentle redirection, like offering a snack, playing familiar music, or suggesting a simple activity, works better than reasoning or restraint. Physical comfort checks are worth doing every time: is the person too warm, in pain, hungry, or needing the bathroom?
The Role of Melatonin
Because melatonin levels are significantly reduced in people with dementia, supplemental melatonin has been studied as a potential tool for sundowning. Early research found that low doses (ranging from 0.3 to 3 mg before bedtime) helped correct circadian rhythm disruptions in some patients and reduced the time it took to fall asleep. Results have been mixed across studies, though, and higher doses don’t necessarily work better. Some trials found no benefit at very low doses while others found modest improvements in sleep quality at higher ones.
Melatonin is generally well tolerated, but its effectiveness for sundowning specifically, as opposed to general sleep improvement, is still not firmly established. It’s worth discussing with a healthcare provider, particularly since sleep medications commonly prescribed to older adults carry significant risks of falls and increased confusion.
Why Sundowning Can Signal Progression
For many families, the onset of sundowning is the first sign that dementia has moved from an early stage into moderate territory. If your loved one has recently started showing late-day agitation or confusion that wasn’t present before, this shift likely reflects advancing damage to the brain’s internal clock and emotional regulation systems. It doesn’t mean the person has suddenly jumped to late-stage dementia. It means the disease is progressing through the middle stages, which is when sundowning is most active and most manageable with the right environmental support.