Why Is Dementia Worse in the Evening? Sundowning Explained (and What Actually Helps)
Dementia often feels harder in the late afternoon and evening because of "sundowning": rising confusion, restlessness or distress as daylight fades. It is common but not universal, and nobody fully understands why it happens. A 2025 review found estimates ranging from under 2% to over 60% of people with dementia, depending on how it is defined. The encouraging part is that likely triggers, such as tiredness, hunger, pain, infection, shadows and an over-busy afternoon, can often be found and eased. This guide explains what the research shows, what NICE advises about light, sleep and medicines, and what helps in practice. With the clocks having gone back on 25 October, many families are noticing earlier, harder evenings.
*Last reviewed: 11 November 2026. Sources include NICE, the Alzheimer's Society, an NHS patient leaflet and peer-reviewed reviews. This is general information and does not replace advice from a GP or nurse.
What Is Sundowning, and Why Does Dementia Seem Worse in the Evening?
Sundowning is a pattern of increased confusion, agitation or anxiety that appears in the late afternoon or evening. An NHS patient leaflet from October 2025 describes symptoms that are less pronounced earlier in the day, typically between 4.30 pm and 11 pm. It is most likely in mid-stage to advanced dementia.
It looks different from person to person. Someone may pace, ask repeatedly to go home, become suspicious or tearful, or resist help with washing and bedtime. Some people see or hear things that are not there.
It is not a diagnosis in its own right. The 2025 review in the *Journal of Clinical Medicine* notes that there is still no agreed-upon definition, which partly explains the wide range in how common it appears.
How Common Is Sundowning? What the Latest Research Says
Nobody can give a single reliable figure. The 2025 review reports prevalence rates from 1.6% to 66% of people with dementia, depending on the study. It also notes that the problem is an important reason for people moving into nursing facilities.
Setting matters too. An earlier review described sundowning as the second most common disruptive behaviour in institutional settings, after wandering. Some data suggest it occurs more in autumn and winter, when dusk arrives earlier.
The practical point is that you are not alone, and it is not a sign that you are doing something wrong. It is a recognised feature of dementia that care can often soften.
What Triggers Sundowning?
The causes are not well understood and probably differ between people. The Alzheimer's Society lists tiredness, hunger, pain and other unmet physical needs among the possible causes, and advises working out which one is affecting the person, as each may need a different response.
Other plausible triggers include:
- Light and shadows. Dim light can make a familiar room look unfamiliar. A 2022 review of care home studies found that insufficient natural light exposure was associated with worse behavioural symptoms and disrupted daily rhythms, though it was unclear exactly how light acts.
- A tiring day. A busy, noisy afternoon can leave someone with little capacity to cope by evening.
- Body clock changes. Dementia can disrupt sleep-wake rhythms.
- Sensory loss. Poor hearing or sight makes dusk more confusing.
- Illness or medication. Infections and side effects can both worsen confusion.
Is It Sundowning or Something Else? When to Call a GP
A sudden change needs medical attention. New or rapidly worsening confusion can be delirium, a medical problem often caused by infection, pain or medication, which needs prompt assessment. It should not be written off as dementia progressing.
NICE's dementia guideline says people with distressing symptoms should be assessed as early as possible for contributing factors, including physical health, possible undetected pain or discomfort, medication side effects, depression, personal history and the environment.
Call your GP or 111 for a sudden change, and 999 if there is immediate danger. Hallucinations that appear alongside movement problems may point to Lewy body dementia, which needs specialist advice.
What Actually Helps? A Practical Evening Plan
Start with the day, not the evening. NICE recommends considering a personalised, multicomponent approach to sleep problems in dementia, including sleep hygiene education, exposure to daylight, exercise and personalised activities.
In practice:
- Get daylight and movement earlier. A morning walk or time near a window helps, and leaves energy for the evening.
- Keep a steady routine. Meals, activities and bedtime at similar times reduce uncertainty.
- Meet needs before dusk. Offer a drink, snack, toilet visit and pain relief where prescribed.
- Soften the evening. Switch on warm, even lighting before it gets dark, close curtains, and reduce noise and busy television.
- Offer calm connection. Familiar music, a hand massage or a favourite photograph can settle someone.
During an episode, the NHS leaflet advises staying calm, reminding the person what time of day it is, not arguing and reassuring them. Our guide to reminiscence therapy explains how familiar memories can comfort.
What About Light Therapy, Melatonin and Medication?
The evidence is mixed. Bright light therapy is widely discussed, but reviews describe the evidence as limited, and the 2022 review above suggests that natural daylight and a well-lit environment may matter more than devices.
On medicines, NICE is clear. Melatonin should not be used to manage insomnia in people with Alzheimer's disease. Antipsychotics should only be offered if someone is at risk of harming themselves or others, or is severely distressed by agitation, hallucinations or delusions. If used, they should be at the lowest effective dose for the shortest time, with a review at least every six weeks. NICE also warns that antipsychotics can worsen movement symptoms in people with Lewy body dementia or Parkinson's disease dementia.
Never start or stop a medicine without speaking to the prescriber.
Why Does the Care Environment Matter So Much?
Because many triggers are environmental, small design and routine choices add up. Good lighting, calm communal spaces, activity earlier in the day, consistent staff and a pace that slows towards evening can all reduce distress.
It also helps to have trained people present who can spot a medical cause. Staff who know someone well notice early signs, such as a new limp or less appetite, and can involve a GP quickly.
Sundowning may be a sign that needs are rising. Our guides to the stages of dementia and when someone needs 24-hour nursing care explain when extra support helps.
Frequently Asked Questions
What time does sundowning start?
Usually in the late afternoon and lasts into the evening, typically between about 4.30pm and 11pm, though timing varies.
What stage of dementia does sundowning happen in?
Most often in mid-stage to advanced dementia, but it can occur at other stages.
What triggers sundowning?
Possible triggers include tiredness, hunger, pain, infection, poor lighting, noise, sensory loss, medication effects and changes in the body clock.
How do you calm someone with sundowning?
Stay calm, reassure them, do not argue, remind them of the time of day, and meet physical needs such as thirst or hunger.
Does melatonin help with sundowning?
NICE says melatonin should not be used to manage insomnia in people with Alzheimer's disease. Speak to a GP before taking any supplement.
When should I worry about sudden confusion?
New or rapidly worsening confusion can signal delirium or infection. Contact your GP or 111, and call 999 in an emergency.
How Does Manor House Support Calmer Evenings?
Manor House Care Home in Stafford provides specialist dementia care alongside nursing, mental health, palliative and respite care. Residents can take part in an activities programme, spend time in the sensory herb garden and relax in comfortable lounges.
You can read about what specialist dementia care involves, meet the team, see the CQC report or browse the FAQs.
If evenings are becoming harder for someone you love, please call the team at Manor House on 01785 250 600. We are happy to listen, talk through what might help and show you around whenever you feel ready.