Why Your Loved One With Dementia Gets Worse in the Evening (Sundowning Explained)

Have you noticed that the afternoons and evenings are the hardest part of your day? That your loved one can seem relatively calm in the morning, but by 4:00 or 5:00 PM something shifts? They become more confused, more agitated, more suspicious, and nothing you say or do seems to reach them.

Or maybe it is the nights wearing you down. Your loved one wakes at 2:00 AM convinced it is time to start the day. You explain, again and again, that it is the middle of the night. They do not believe you. And while they sleep the afternoon away, you are running on a kind of exhaustion that does not have a name.

If any of this sounds familiar, I want you to know: this is not something you are doing wrong. This is something happening in your loved one’s brain. And now, science is giving us a clearer neurological explanation for why.

What Is Sundowning in Dementia?

Sundowning is the term used to describe a pattern seen in many people with dementia: increased confusion, agitation, anxiety, or restlessness as the day goes on, often peaking in the late afternoon or early evening.

It does not happen to everyone with dementia. But for those it does affect, it tends to be consistent and predictable, almost like a daily alarm going off in the brain.

The word “sundowning” can feel clinical and distant when you are the one living through it every day. What caregivers actually experience looks more like this:

• A loved one who is recognizable in the morning but unreachable by dinnertime
• Repeated questions, pacing, distress, or attempts to leave
• Suspicion, fear, or a certainty that something is terribly wrong
• A spouse or parent who insists they need to go home, even when they are already home

And that swing from okay to not okay, the dramatic shift that can happen in a matter of hours, can make a caregiver feel like they are somehow causing it. You notice it starts at the same time each day. You try to think of what you did differently. You wonder what you missed.

I want to say this clearly: you did not cause this. The consistency of the timing is not a clue that points to something you are doing. It is a clue that points to something happening in the brain.

When Sleep Gets Turned Upside Down

Closely related to sundowning, though not exactly the same, is what many caregivers describe as the day-night flip.

Your loved one sleeps through much of the afternoon and is fully alert at 2:00 AM. They are not doing this intentionally. Their internal sense of when to be awake and when to sleep has become disoriented. The brain that normally regulates waking and sleeping is no longer sending reliable signals.

When that happens, you are not sleeping either.

If you are the primary caregiver, that means you are making care decisions, managing medications, handling middle-of-the-night confusion, and showing up again the next morning while running on almost no rest. Chronic sleep deprivation is not just uncomfortable. It affects your judgment, your emotional steadiness, and your physical health in ways that compound over time.

There is no amount of love or commitment that makes this indefinitely sustainable. I want to be honest about that, and I will come back to it.

What You Might Be Telling Yourself

Inside our support rooms, I hear caregivers say things like:

“Why does she get so much worse at 4:00 PM? What am I doing wrong?”

“He is up all night and sleeps all day. I have no idea how to keep going.”

“She is fine during the day and by evening she is a completely different person. I feel like I am losing my mind.”

Does any of this sound familiar?

I want to be clear, because I know there is a lot of talk about how what we do, what we say, how we present can sometimes trigger our loved ones. But in this situation, it is not something you are saying or doing that is causing the sundowning.

It is not about you at all. It is about what is happening in your loved one’s brain.

A New Neurological Explanation: What the Research Now Shows

In late 2025, a study was published in Neurology, the medical journal of the American Academy of Neurology. This study followed more than 2,000 older adults over several years. At the start of the study, none of the participants had dementia.

Each participant wore a small chest patch that tracked their circadian rhythm, the body’s internal 24-hour clock that regulates when we feel awake, when we feel tired, when we release hormones, and when we naturally shift toward sleep.

Here is what the researchers found.

Participants whose circadian rhythms were weak and irregular had nearly two and a half times the risk of developing dementia compared to those with strong, consistent body clocks.

Not slightly higher. Nearly two and a half times.

Around the same time, researchers at the University of Washington School of Medicine found that amyloid plaques, the toxic proteins associated with Alzheimer’s disease, also have disrupted circadian patterns. That study was conducted in mice, so we have to be careful about applying it directly to humans. But the direction it points is significant: the disrupted body clock may not just be a symptom of dementia. It may play a role in how the disease progresses.

What This Means: A Broken Internal Clock

So what does this research actually mean for your loved one who already has dementia?

It means that the 24-hour internal clock we all rely on, the system that tells the brain when it is daytime, when it is nighttime, when to be alert, when to rest, is significantly disrupted. Not slightly off. Profoundly disrupted.

Sundowning is not behavioral. It is not manipulative. It is not your loved one choosing to be more difficult in the evenings.

It is their brain’s broken clock system sending wrong signals at the wrong time. Their nervous system is doing its best to respond to information that is no longer reliable.

This reframes everything. Your loved one at 4:00 PM, confused and distressed, is not making a choice. Their brain is receiving a faulty signal, and their body is responding to it. Just as other unexpected dementia behaviors, like personality shifts or emotional outbursts, are not character flaws but neurological events, sundowning is the result of a brain system that is no longer working as it should. You can read more about how dementia changes behavior in ways that feel personal but are not in this post on why some people with dementia become mean.

Five Things That Can Help

There is no magic fix for sundowning. I want to be honest about that. But there are approaches that work with the biology of the circadian system rather than against it, and over time, they can make a real difference.

1. Morning Bright Light

Research consistently points to morning bright light exposure as the most studied non-pharmacological strategy for supporting the circadian system in people with dementia. Light is the primary input that sets the body’s internal clock. Getting your loved one into natural sunlight in the morning, even briefly, sends a direct signal to the brain: it is daytime.

If you live somewhere sunlight is limited, or the season makes morning light scarce, a light therapy box placed nearby during morning hours is worth considering. This is not a cure. But it is working with biology rather than ignoring it, and that matters.

2. Keep the Schedule Consistent

When the day follows a reliable rhythm, the brain does not have to work as hard to orient itself. Wake at roughly the same time. Eat at roughly the same time. Begin the wind-down routine at roughly the same time each evening.

Even loose consistency helps. A brain that has lost its internal clock relies more heavily on external cues. Predictable structure becomes one of those cues.

3. Reduce Stimulation and Light as Evening Approaches

As afternoon shifts toward evening, begin lowering lights and reducing noise. Bright overhead lights in the evening are sending a direct signal to your loved one’s brain: it is midday, stay alert, do not rest.

Think of it as sending your loved one’s brain the message: “It’s safe to rest now.” Quieter spaces, familiar activity, softer sounds. Less stimulation, not more.

4. Reframe What Is Happening

This one matters as much as any practical strategy. When sundowning begins, the instinct is often to try to fix it, to reason with your loved one, to explain the time, to stop what is happening. But their brain does not have access to the logic and orientation functions that would allow any of that to land.

Instead of: “Oh no, what now? What did I do to cause this?”

Try: “Yep, it is 4:00. Their brain is having a hard time. Their internal clock is totally disrupted.” It is not about you. It is not about them. It is about this internal body clock that does not realize what time it is.

And so instead of feeling like you have to stop this right away or fix it right away, it might be reframing it as: “Okay. We are going to ride through this in the most calm way possible.”

5. Take Your Own Sleep Seriously

I want you to hear this.

If you are not sleeping, you are not okay.

It is not about how strong you are. There is no human being who can sustain chronic sleep deprivation indefinitely. This is the moment to think seriously about respite care, about rotating coverage with other family members or friends, about talking to a social worker or healthcare provider about what options exist for nighttime support. Your sleep is not a luxury. It is a foundational part of your ability to keep giving care.

Responses That Often Make Things Harder

Some reactions are completely understandable and still tend to make sundowning worse.

Trying to reason your loved one out of sundowning, explaining that it is not nighttime yet, telling them to calm down, pointing out that they were just fine an hour ago. These approaches require brain functions that dementia disrupts. The reasoning, orientation, and logic centers are not working reliably. Asking your loved one to use those functions is asking them to do something their brain is no longer capable of.

Getting louder or busier as the sundowning escalates is another natural but counterproductive response. When someone with dementia becomes dysregulated, more stimulation does not help. Their nervous system needs less input, not more. Quiet presence. Gentle company. Soft, familiar music. Sometimes the most powerful thing we can offer in these moments is just stillness.

And bright lights left on throughout the evening are working against you. Every hour of bright overhead lighting is communicating to the already-confused brain: stay awake, stay alert, it is not time to rest.

This Is Not a Small Thing to Live Through

Understanding the science of sundowning is one thing.

Living through it, night after night, is another.

You may have started dreading late afternoon before it even arrives, watching the clock, bracing for what you know is coming. Just because research has given us a neurological framework for why this happens does not make it any easier to carry.

Careblazer, you are doing an incredibly difficult but meaningful job in caring for your loved one. The fact that you are still looking for answers, still trying to understand what is happening, still searching for something that might help. That is not small work.

You do not have to carry it alone.

Inside the Care Collective, we talk about exactly these kinds of situations. Not just what is happening in the brain, but how to respond in real life, how to cope with the emotional impact, and how to take care of yourself while still caring for your loved one. You can learn more here.

Sources & References

• Association Between Circadian Rest-Activity Rhythms and Incident Dementia in Older Adults — Neurology (December 2025)
• Sleep Issues and Sundowning — Alzheimer’s Association
• Light, Sleep-Wake Rhythm, and Behavioral Symptoms of Dementia — PMC Review
• Coping With Agitation and Sundowning in Alzheimer’s Disease — National Institute on Aging