Dog Sundowning: Why Senior Dogs Get Confused and Restless at Night

Understanding Sundowning: Why Your Senior Dog Is Restless and Confused at Night

If your older dog paces the hallway at dusk, stares at walls, or whines and cannot settle once the sun goes down, you are seeing what many owners call sundowning — a pattern of confusion, restlessness, and anxiety that ramps up in the late afternoon, evening, and overnight. In dogs, this evening restlessness is most often an early face of Canine Cognitive Dysfunction (CCD), the dog version of age-related dementia. The reassuring part: it is common, it is manageable, and understanding it is the first step to helping your dog — and your whole household — rest easier.

CCD is genuinely common in senior dogs, and it climbs steeply with age. A Colorado State University survey of older dogs found presumptive advanced cognitive dysfunction in 8.1% of dogs aged 8 to under 11 years, 18.8% at 11 to under 13, 45.3% at 13 to under 15, and 67.3% at 15 to under 17 years [1]. If your gray-muzzled companion seems disoriented in the evenings, you are far from alone — and it is worth taking seriously rather than writing it off as just getting old.

What Sundowning Looks Like in Dogs

Sundowning is not one single symptom; it is a cluster of evening and nighttime behaviors, which can include:

• Restlessness and pacing — walking in circles or back and forth, unable to lie down and stay down.
• Disorientation — getting stuck in corners or behind furniture, standing on the wrong side of a door, or seeming lost in familiar rooms.
• Vocalizing — barking, whining, or howling at night, sometimes at nothing in particular.
• Reversed sleep — sleeping more during the day and then being wakeful, anxious, and active at night.
• Clinginess or agitation — following you around, panting, or being unable to relax as the light fades.

For a broader look at the daytime and behavioral changes that often accompany these hard nights, see our guide to the signs of dog dementia.

Sundowning Is Usually Part of Canine Cognitive Dysfunction

Veterinarians screen for CCD using the DISHAA framework, which captures the domains where aging brains change: Disorientation, altered Interactions with people or other pets, Sleep-wake cycle changes, House-soiling or loss of house-training, Activity changes such as more pacing or less engagement, and increased Anxiety. Sundowning lives mostly in the sleep-wake and anxiety domains of that framework, but dogs with evening restlessness often show other DISHAA signs too.

These changes are more common than many owners realize. According to VCA Animal Hospitals, 28% of owners with dogs aged 11 to 12 reported at least one DISHAA sign, and that number rose to 68% of owners with dogs aged 15 to 16 [2]. Spotting the pattern early gives you the best chance to slow it down.

Why Sundowning Happens

CCD is a true neurodegenerative disease — the canine parallel to Alzheimer's. As the brain ages, a sticky, brain-damaging protein called beta-amyloid builds up; these plaques are neurotoxic and interfere with normal nerve signaling, and the severity of a dog's cognitive decline tends to track with how much beta-amyloid has accumulated [3]. Oxidative damage from free radicals adds to the injury, gradually wearing down the brain circuits that regulate sleep, orientation, and calm. Evenings are often the hardest window because fading light removes the visual cues an already-confused brain was leaning on, and a full day's fatigue lowers a dog's ability to cope.

First, Rule Out the Look-Alikes

This is the most important step, and it is why a vet visit comes before any home remedy: several treatable medical problems can mimic or worsen sundowning, and they need to be caught first. Cornell University's Riney Canine Health Center notes that a veterinarian will perform a thorough physical exam and check blood and urine tests to rule out other conditions with similar signs, such as pain, arthritis, seizure disorders, systemic illnesses, and vision or hearing loss [4].

Arthritis pain, for instance, can leave a dog restless and unable to settle at night — our guide to senior dog arthritis covers how joint pain shows up in older dogs. A urinary tract infection can drive nighttime house-soiling, failing eyesight or hearing can cause startled and lost behavior, and endocrine disease or high blood pressure can shift activity and sleep. Because these causes are often fixable, new-onset confusion should always begin with a veterinary workup rather than a guess.

What Helps: Managing Sundowning

Once treatable causes are ruled out, most dogs improve with a combination of environmental management, diet, and — when appropriate — medication. No single fix works alone; the combination is what makes the difference.

Build a calm, predictable routine

Structure is medicine for a confused brain. Keep feeding, walks, and bedtime on a consistent daily schedule, offer gentle daytime enrichment and mental stimulation, and try to channel your dog's energy earlier in the day. Today's Veterinary Practice notes that maintaining a regular routine can reduce anxiety, and that increasing daytime exercise while reducing evening disturbances helps address nighttime waking [5]. Practical touches many owners find useful include night lights along your dog's usual path, a cozy and enclosed resting spot to settle into, non-slip footing, and a reliable potty break right before bed.

Diet and supplements with evidence

Nutrition genuinely moves the needle here. Diets and supplements studied for canine cognitive dysfunction include medium-chain triglycerides (MCTs), which give the aging brain an alternative energy source; antioxidants such as vitamins E and C; omega-3 fatty acids; and SAMe. Today's Veterinary Practice reports that dogs fed an MCT-supplemented diet performed better on cognitive tasks, that an antioxidant-enriched brain-support diet slowed the rate of cognitive decline over a 2-year study (with the greatest benefit when paired with enrichment), and that dogs given SAMe showed increased activity and interaction with their owners in a placebo-controlled trial [6]. Ask your vet which senior brain-support diet or supplement fits your dog, and do not add supplements on your own, since some interact with medications.

Prescription options your vet may consider

For dogs whose signs are more advanced, veterinarians can prescribe medication. Selegiline (brand name Anipryl) is the only drug FDA-approved specifically for canine cognitive dysfunction; according to Veterinary Partner, this MAO-inhibitor class of drug may help brain neurons communicate with one another and offer some protection to the brain [7]. Vets may also use anti-anxiety medications or melatonin to smooth out the nights. These are vet-directed decisions, and the right dose depends on your individual dog — so never medicate without your veterinarian's guidance.

If your dog's confusion is also affecting appetite, our article on dog dementia and not eating goes deeper, and because muscle wasting often travels with old age, senior dog muscle loss is worth a read too.

When to See a Vet

• New confusion or restlessness in an older dog always warrants a veterinary workup — it is the only way to rule out treatable causes such as pain, infection, endocrine disease, or sensory loss before assuming dementia.
• Sudden or rapidly worsening changes — a fast decline over days, disorientation with constant circling, head-pressing, or seizures needs prompt evaluation.
• Distress or self-injury — if your dog is panicked, hurting themselves while pacing, or so anxious they cannot rest at all, do not wait it out.
• Not eating or drinking — refusing food or water, or any sudden drop in appetite alongside the behavior change, should be seen promptly.

Frequently Asked Questions

Is sundowning the same as dog dementia? Not exactly. Sundowning describes the evening-and-nighttime pattern of confusion and restlessness, while canine cognitive dysfunction (CCD) is the underlying brain disease. Veterinary Partner describes CCD as essentially the dog equivalent of Alzheimer's disease, and sundowning is one of the ways it shows up. You can learn more in our dog dementia signs guide.

At what age do dogs start sundowning? Risk rises sharply with age. A Colorado State University survey found presumptive advanced cognitive dysfunction in about 8.1% of dogs aged 8 to under 11 years, climbing to 45.3% by 13 to under 15 and 67.3% by 15 to under 17 years. Most sundowning appears in the senior and geriatric years, but earlier, subtler signs are easy to miss.

Why is my old dog restless and pacing only at night? A disrupted sleep-wake cycle is a hallmark of CCD — affected dogs often sleep more by day and become wakeful and anxious at night. But nighttime restlessness can also come from pain, a full bladder, or vision loss. Cornell's Riney Canine Health Center recommends a vet exam with blood and urine tests to rule out look-alike conditions such as pain, arthritis, and sensory loss first.

Can dog sundowning be cured? There is no cure for canine cognitive dysfunction, but progression can often be slowed and the symptoms managed. As Today's Veterinary Practice describes, the most effective approach combines a consistent routine and enrichment with a brain-support diet and, when needed, prescription medication.

What diet or supplements help a dog with sundowning? Options with study support include MCT-enriched brain-support diets, antioxidants such as vitamins E and C, omega-3 fatty acids, and SAMe. Today's Veterinary Practice reports that MCT diets improved dogs' cognitive-test performance and that an antioxidant brain diet slowed cognitive decline over a 2-year study. Always choose these with your veterinarian, as some supplements interact with medications.

Is there a medication for dog sundowning? Yes — for more advanced cases, veterinarians may prescribe selegiline (Anipryl), which is the only drug FDA-approved specifically for canine cognitive dysfunction; Veterinary Partner notes this MAO-inhibitor may help brain cells communicate and protect the brain. Anti-anxiety medications or melatonin are sometimes added for the nights. All of these are vet-directed, and dosing must come from your veterinarian.

References

1. MacQuiddy B, et al. Assessment of Risk Factors in Dogs With Presumptive Advanced Canine Cognitive Dysfunction. Frontiers in Veterinary Science (2022)
2. VCA Animal Hospitals — Senior Pet Cognitive Dysfunction
3. Today's Veterinary Practice — Updates on Cognitive Dysfunction Syndrome (2024)
4. Cornell University College of Veterinary Medicine, Riney Canine Health Center — Cognitive Dysfunction Syndrome
5. Today's Veterinary Practice — Management of Dogs and Cats With Cognitive Dysfunction
6. Today's Veterinary Practice — Nutritional Intervention for Canine Cognitive Dysfunction
7. Veterinary Partner (VIN) — Cognitive Dysfunction Syndrome in Dogs