Why Is My Dog Pacing at Night? Dementia, Anxiety & Other Causes

All day she was fine. Napped in her usual spot, ate normally, greeted you at the door like always. Then the sun started going down, and something shifted. She started pacing in tight little loops between the kitchen and the hallway. She stood staring at a blank wall for almost a minute. When you called her name she looked at you like she wasn't quite sure who you were for a second. Now it's 9pm and she won't settle — panting, whining at the door, wandering into rooms and just... standing there.

If this is starting to feel like a pattern — fine by day, unraveling by evening — you may have already come across the term for it while searching tonight: sundowning. It's not a word made up by worried pet forums. It's a real, recognized pattern in aging dogs, and it has a name because it's common enough that vets see it constantly.

I want to walk you through exactly what sundowning is, why it happens specifically in the evening and night, how it connects to canine cognitive dysfunction, how to tell it apart from pain or other medical causes that can look similar, and what actually helps — both the changes you can make tonight and the treatment options your vet can offer.

What Sundowning in Dogs Actually Is

Sundowning is a term borrowed directly from human dementia care, where patients with Alzheimer's often become more confused and agitated as daylight fades. Vets and researchers use the same word for dogs because the pattern is strikingly similar: a dog who seems completely normal during the day but becomes restless, anxious, or disoriented in the late afternoon, evening, or overnight.

Sundowning itself isn't a separate disease — it's a symptom pattern that shows up within a broader condition called Canine Cognitive Dysfunction (CCD), sometimes called canine dementia. CCD is a progressive, age-related decline in brain function, most often appearing from around 9 years old onward, and it's genuinely common — studies estimate a meaningful share of senior dogs show at least some signs, even though many cases go unrecognized because the early signs are subtle and easy to write off as "just getting older."

Why It Happens in the Evening Specifically

The honest answer is that researchers don't have this fully mapped out, but the leading explanation involves the dog's internal body clock (circadian rhythm) and how the aging brain processes light. As daylight fades and the environment gets darker and quieter, a healthy brain smoothly shifts toward rest. In a brain affected by cognitive dysfunction, that transition doesn't happen cleanly — instead of winding down, the dog can become more confused and anxious right as the visual and environmental cues that normally orient them start disappearing.

There's also a simpler, compounding factor: many dogs with CCD sleep more during the day, which shifts their internal clock further out of sync with yours, making nighttime wakefulness and confusion more likely.

The Signs — What Sundowning Actually Looks Like

Vets often use the acronym DISHA to describe the full pattern of cognitive dysfunction, and sundowning tends to show several of these signs concentrated into the evening and night hours specifically:

• Disorientation — staring at walls or corners, getting "stuck" behind furniture, appearing lost in familiar rooms

• Social interaction changes — seeming not to recognize you for a moment, increased clinginess, or unusual withdrawal

• Sleep-wake cycle changes — sleeping heavily during the day, then restless or awake for stretches at night

• House-soiling — accidents indoors despite being fully house-trained for years

• Activity changes — pacing, repetitive movement, or in some dogs, reduced activity and general aimlessness

The anxiety piece — panting, whining, pacing, an inability to settle — is often what owners notice first and describe most vividly, because it's the most visible and the most disruptive to everyone's sleep.

Ruling Out Look-Alikes First

Before assuming sundowning, it's worth knowing that several other conditions can produce a very similar evening pattern, and your vet will want to rule these out:

• Pain — arthritis and joint pain often feel worse after a day of activity and once a dog lies still, which can look identical to restlessness from confusion

• Vision or hearing loss — reduced senses make a dog more reliant on visual light cues, so dim evening light can genuinely disorient a dog with cataracts or vision decline in a way that mimics cognitive symptoms

• Urinary tract infection — infections can cause nighttime restlessness and discomfort that looks behavioral but has a simple, treatable medical cause

• Intracranial disease — less commonly, a brain tumor or other neurological condition can present with similar evening confusion

This is exactly why a vet visit matters here rather than assuming it's "just" cognitive decline — some of these look-alikes have quick, complete fixes.

When to See a Vet Promptly

• The restlessness or confusion is new, sudden, or worsening quickly rather than gradual

• Your dog seems to be in pain — yelping, reluctance to move, stiffness

• There are signs of a UTI — straining to urinate, blood in urine, frequent small urinations

• Disorientation extends into daytime hours, not just evening

• Your dog seems distressed rather than simply restless — this is worth addressing quickly for their comfort as much as yours

How Vets Diagnose Cognitive Dysfunction

There's no single blood test or scan that confirms CCD. Instead, diagnosis is made by ruling out other medical causes (bloodwork, urinalysis, a full physical and neurological exam) and then scoring your dog's symptoms against standardized behavioral questionnaires that vets use specifically for this purpose. This is part of why keeping a simple log of what you're seeing — what happens, roughly what time, how often — genuinely speeds up getting an accurate diagnosis.

Treatment Options

• Selegiline (Anipryl) — the only medication specifically labeled for canine cognitive dysfunction, it supports dopamine activity in the brain and shows improvement in a majority of dogs, though full effect can take several weeks

• Prescription cognitive diets — formulated with antioxidants and specific fatty acids shown to support brain function over time, with some dogs showing improvement within a couple of months

• Anti-anxiety medication — for dogs where nighttime distress is severe, your vet may add a short-term anxiety medication alongside the underlying CCD treatment

• Melatonin — sometimes used under veterinary guidance to help reset disrupted sleep-wake cycles

• Environmental and routine changes — covered in detail below, and often the first thing your vet will help you build a plan around

What You Can Do at Home Tonight

• Keep evening lighting soft but consistent — deep shadows and sudden darkness make disorientation worse; a dim, steady light source helps more than total darkness or bright light

• Stick to a predictable evening routine — same time for dinner, same walk pattern, same wind-down sequence, since predictability itself is calming for a confused brain

• Add daytime mental and physical activity — a more engaged day can improve nighttime sleep quality, though avoid intense exercise right before bed

• Block off hazards — baby gates on stairs or around furniture with sharp corners reduce injury risk during nighttime pacing and confusion

• Stay calm when you respond — your dog can pick up on your own stress, and a calm, steady presence helps more than trying to "fix" the confusion in the moment

A Final Word From Dr. Waleed

Sundowning is genuinely one of the harder things to watch as an owner, because your dog isn't in obvious physical pain, but they're clearly distressed, and there's no quick fix that ends it in a day. I want to be honest with you: this is usually a manageable, gradual condition rather than a medical emergency, and most dogs with a treatment plan in place — medication, routine, and a calmer evening environment — settle noticeably within weeks. You're not imagining this pattern, and you're not failing your dog by finding it exhausting. Bring your vet into this early; the earlier cognitive dysfunction is addressed, the more comfortable those evening hours can become for both of you.

Frequently Asked Questions

What is sundowning in dogs?

Sundowning is a pattern of increased confusion, restlessness, and anxiety that occurs in aging dogs during the late afternoon, evening, or night. It's a symptom pattern within canine cognitive dysfunction (CCD), the dog equivalent of dementia, rather than a separate disease on its own.

At what age do dogs start sundowning?

Signs of canine cognitive dysfunction, including sundowning, most commonly begin appearing from around 9 years of age onward, though this varies by dog and breed size.

Can sundowning in dogs be cured?

No, canine cognitive dysfunction is not curable, but it is very manageable. Medication, prescription diets, routine changes, and environmental adjustments can meaningfully reduce symptoms and slow progression for many dogs.

Is sundowning in dogs painful?

Sundowning itself isn't physically painful, but it can be genuinely distressing for the dog experiencing the confusion and anxiety. It's also important to rule out pain from arthritis or other conditions, since pain can produce similar evening restlessness.

What's the difference between sundowning and separation anxiety in dogs?

Separation anxiety is specifically triggered by being left alone and tends to occur at any time of day. Sundowning follows the daily light cycle and typically happens whether or not you're present, worsening specifically as daylight fades.

Does melatonin help dogs with sundowning?

Melatonin is sometimes used under veterinary guidance to help support disrupted sleep-wake cycles in dogs with cognitive dysfunction, though it should be dosed and approved by your vet rather than given on your own, since human melatonin products can contain ingredients unsafe for dogs.

How long does a sundowning episode usually last?

This varies significantly by dog, ranging from an hour or two of restlessness to intermittent unsettled behavior throughout the entire night. Consistent management typically reduces both the frequency and length of episodes over time.

Have a question about your own senior dog? Ask Dr. Waleed directly — every question helps shape the next guide on this blog.

Related reading:
Why Is My Old Dog So Itchy All of a Sudden? A Vet Explains
My Senior Dog Is Drinking a Lot of Water — A Vet Explains Every Cause