Understanding Sundowning in Dementia

If you support someone living with dementia, you may have noticed that their behaviour changes as the day goes on. Many carers describe evenings as particularly challenging, with their loved one becoming more restless, confused, or unsettled. This pattern is often called sundowning.

What is sundowning?

Sundowning isn’t a medical diagnosis — you won’t see it on a GP’s notes — but rather a useful way of describing a collection of behaviours that commonly appear later in the day. It typically happens between late afternoon and bedtime, especially in the autumn and winter when daylight fades earlier.

Although not fully understood, sundowning is widely recognised by carers and professionals as a real and difficult part of living with dementia.

Signs you might notice

During an episode of sundowning, someone may:

Seem unusually agitated or anxious
Pace around or appear restless
Express a strong desire to “go home” even when they are already at home
Call out for relatives who have passed away
Want to find a particular person or place
Leave the house unexpectedly
Show suspicion or paranoia
Struggle to recognise familiar surroundings
Experience more frequent hallucinations

These behaviours can vary, but the common theme is a noticeable shift from the person’s usual state.

The impact on carers

Evenings can be exhausting. As a carer, this might be the time when you’re also feeling worn out, trying to make dinner, helping children with homework, or juggling other responsibilities. Facing a loved one’s increased distress on top of your own fatigue can feel overwhelming. It’s important to acknowledge that sundowning doesn’t just affect the person with dementia — it places a real emotional and physical strain on those providing care.

Why does sundowning happen?

Researchers believe sundowning is linked to a mix of factors, including:

Body clock changes – Dementia can disrupt circadian rhythms, the internal “clock” that tells our bodies when to wake, rest, and sleep.
Temperature shifts – Our body temperature naturally rises in the evening, and changes in regulation may contribute to discomfort.
Light levels – Shorter days and lower light can make it harder for someone with dementia to interpret their surroundings, sometimes mistaking shadows or shapes for something frightening.
Hunger and low blood sugar – Being tired, hungry or thirsty can affect mood and behaviour, just as it does for anyone else.
Pain – Aches or discomfort (especially before medication is due) can become more noticeable later in the day.
Boredom – Without enough meaningful activity, evenings can feel empty or unsettling, particularly for those used to busy routines.
Lack of activity: When the day doesn’t include enough meaningful activity, restlessness and agitation can build up by evening.
Limited exposure to natural daylight: Not spending time in natural light can disrupt the body’s internal clock, making late afternoons and evenings more confusing.
Overstimulation: Too much noise or activity during the day can overwhelm someone with dementia, leading to increased distress as the day winds down.

Supporting someone through sundowning

While there’s no single solution, there are practical steps that may help:

Keep a routine – A predictable daily rhythm can be reassuring and reduce confusion.
Encourage good sleep habits – Aim for restful sleep, and seek professional advice if disturbed sleep becomes ongoing.
Manage pain – If pain is suspected, speak to a GP, nurse, or another health professional.
Use lighting effectively – Close curtains before dusk and ensure rooms are well lit to reduce shadows and distortions.
Provide meaningful activity – Gentle exercise, creative tasks, or activities linked to past interests can give structure to the day and reduce evening agitation.

Final thoughts

Sundowning can be one of the most testing aspects of caring for someone with dementia. Understanding why it might be happening, and experimenting with strategies to ease it, can make evenings a little calmer for both the person living with dementia and those supporting them.