Posted by ZNOOZ Marketing
on October 21, 2026
Written by the ZNOOZ marketing team from the veterinary sources listed at the end. We are not veterinarians, and this guide does not replace an exam. ZNOOZ makes the orthopedic bed mentioned in the last section, so we are not a neutral party there.
If your older dog seems like herself in the afternoon but lost, anxious or wide awake by bedtime, you are probably seeing what owners call sundowning. It wears everyone down, and it is easy to dismiss as "just getting old." There is more you can do than most owners expect. This guide covers what sundowning is, the signs to track, what to rule out first, a night plan built from veterinary guidance, and what to ask your vet.
What Is Sundowning in Dogs?
Sundowning is the informal name for symptoms that get worse in the evening and overnight. Cornell University's College of Veterinary Medicine describes it as worsening symptoms and irritability that occur at night, and links it to cognitive dysfunction syndrome (CDS), an age-related brain disease often called dog dementia. Cornell
CDS comes from gradual, age-related changes in the brain, and Cornell compares it to Alzheimer's disease in people. Dogs may begin to show it around age nine or older. Because the changes build slowly and owners may assume they are normal aging, the condition may be underdiagnosed. Cornell Large dogs age faster than small dogs, and the veterinary behaviorists writing for VCA Animal Hospitals say experts recommend annual screening for CDS starting at age 7. VCA
The Six Signs Vets Look For
Veterinarians use the acronym DISHAA to remember the common signs of CDS in dogs. VCA's behaviorists advise that a dog showing more than one of these may be experiencing more than routine aging and should have a physical and behavioral evaluation. VCA Here is how each one tends to look after dark.
| Sign | What it means | What you might see at night |
|---|---|---|
| Disorientation | Getting lost in familiar places, stuck in corners, staring into space | Standing at the wrong side of a door, facing a wall or a corner |
| Interactions | Clingier or more distant than usual, or not recognizing familiar people | Following you from room to room, or hiding when someone comes in |
| Sleep and wake cycle | Sleeping more by day, then pacing and wandering at night | Up and walking the house in the middle of the night, sometimes whining, barking or howling |
| House soiling | Accidents in a dog that was reliably house-trained, and forgetting learned cues | Puddles on the bed or floor, or going to the door too late |
| Activity | Restlessness, pacing, or less interest in play | Wandering with no clear purpose, then sleeping through the next day |
| Anxiety | New fears, irritability, distress when left alone | Panic over sounds that never bothered your dog before |
Cornell's behavior specialists note that disrupted sleep is often the first sign families notice, and that a dog who paces, whines or howls at night can keep the whole household on edge while sleeping the next day away. Cornell
Rule Out Other Causes First
Several problems look like sundowning, and some are easier to treat. Cornell says a veterinarian will do a full exam and usually recommend blood and urine tests to rule out pain, arthritis, seizure disorders, other illnesses, and vision or hearing loss, and sometimes an MRI to rule out brain tumors. Cornell VCA gives two everyday examples: a dog with arthritis may not leave a comfortable bed to greet you, and a dog with kidney disease may be unable to hold its bladder. VCA
So night restlessness is not always the brain. Our guide on why dogs pace at night instead of settling walks through four common causes, and how to help an arthritic dog sleep covers the pain side. If your dog also makes a noise as it lies down, see why a dog groans when lying down.
Call your vet promptly if you see any of these
- A sudden loss of balance. Cornell describes vestibular syndrome as a sudden-onset balance problem that is often confused with cognitive dysfunction: circling or a head tilt, trouble standing, nausea, and eyes that move rapidly from side to side. Cornell
- New house soiling. Cornell advises a vet visit first to rule out a bladder infection. Cornell
- Any change that is sudden, fast or severe. Sundowning builds slowly. A fast change deserves a call today, not a wait-and-see week.
A Night Plan That Costs Almost Nothing
Cornell's guidance for senior dogs starts with simple management, and every step below comes from it unless a VCA note is added. These are comfort and safety measures, not a treatment.
Light the path
Add nightlights so a dog who roams at night can see clearly and is less likely to get stuck. Cornell VCA also suggests extra lighting or scent cues when vision starts to fade. VCA
Tire them out gently before bed
For some dogs, an extra walk right before bedtime leads to longer, deeper sleep. Make it a sniffing walk rather than an exercise walk: Cornell notes that many dogs lose some vision and hearing with age but seem to keep their sense of smell almost to the end. Cornell
Keep the day predictable
Older dogs do better with a set routine. Cornell suggests keeping meals, walks and bathroom breaks on a steady schedule, keeping food and water bowls in the same place, and not moving dog beds or furniture. Cornell That last point matters for the bed section below.
Make the house safer after dark
Block off unsafe areas such as stairways and the space behind the couch, where a confused dog can stumble or get trapped. Cornell If your floors are slippery, VCA recommends runners or floor coverings for traction, and a ramp or portable steps for dogs that share furniture with you. VCA We cover the floor side in our traction plan for old dogs on hardwood floors.
Give them a place to opt out
Some dogs want company and some want to be left alone. Cornell suggests respecting that, watching for signs of fatigue when your dog wants company, and keeping a quiet room where your dog can rest, such as a crate in a quiet room. Cornell
Check hearing before you approach
If your dog is asleep and may be losing hearing, speak as you approach and stamp your foot so your dog can feel the vibration through the floor and know you are near. Cornell If vision is the bigger problem, see setting up a bed for a blind dog.
Handle accidents calmly
See the vet first to rule out a bladder infection. If your dog is otherwise healthy, Cornell suggests extra daytime walks, and says "doggy diapers" can work for dogs that tolerate them, as long as you change them often and keep the hair clean and dry to avoid skin sores. Cornell For bedding, see choosing a bed for an incontinent dog.
Keep the brain busy during the day
Both Cornell and VCA recommend daily enrichment: sniff walks, food puzzles, snuffle mats, scent games, and practicing or learning simple tricks. Match the activity to what your dog's body can do. Cornell VCA
Ask Your Vet About Medical Options
Do not start treatment on your own. Cornell says there is no cure for CDS, but early intervention with enrichment, diet and medical management can improve quality of life and may slow progression. Cornell Both Cornell and VCA name selegiline as the prescription medication licensed for CDS in North America. Cornell notes some owners see improvement within three weeks, while many dogs take six weeks. Cornell VCA
Diets with antioxidants and supplements are discussed in the same sources, but VCA says research is limited and Cornell advises checking with your vet before starting any supplement. Cornell also says melatonin helps some dogs, though few studies confirm it, so talk to your vet before using it. Cornell VCA adds that anxiety and frustration can make cognitive signs worse and that a veterinary behaviorist can build a plan for the whole picture. VCA
Keep a Night Log (Copy This Table)
Notes are the most useful thing you can bring to a vet visit. Record each rough night in a table like this one, and keep it for two weeks before the appointment.
| Date | Time up | What you saw | How long | What came before | What helped |
|---|---|---|---|---|---|
| Example: Mon | 2:10 a.m. | Pacing, stuck behind the couch | 40 minutes | Late dinner, thunder earlier | Nightlight, quiet walk |
Cornell also describes a scoring guide veterinarians use: rate each DISHAA area from 0 (no signs) to 3 (severe), then add them up. A total of 4 to 15 is considered mild, 16 to 33 moderate, and above 33 severe. Bring your totals and your log to your vet instead of trying to interpret the score yourself. Cornell
Looking After Yourself
Broken sleep is hard on everyone. If you can, share night duty, keep a dim light and a leash by the door, and decide ahead of time what would make you call the vet instead of waiting it out.
Frequently Asked Questions
Is sundowning the same as dog dementia?
Not exactly. Sundowning describes signs that get worse at night. In dogs it is usually linked to cognitive dysfunction syndrome, but only a veterinarian can tell whether that, pain, or another illness is behind it.
Why is my old dog worse at night?
Changes in the sleep and wake cycle are one of the classic signs of CDS, and dogs often sleep more by day and become restless at night. In dim light a confused dog also has fewer cues to find its way, which is why nightlights are on Cornell's list.
Can sundowning be cured?
Cornell says there is no one treatment or cure for CDS. Early help with enrichment, diet and medication can slow its progress and improve quality of life.
Should I give my dog melatonin?
Ask your veterinarian first. Cornell says melatonin helps some dogs but that few studies confirm its effects.
Will a new bed help my dog sleep?
A bed will not treat cognitive dysfunction. Because routine matters so much, a familiar bed in a familiar spot is usually the better choice. A new bed is worth considering only when the old one is flat, uncomfortable or impossible to keep clean.
If the Bed Itself Has to Change
Cornell's advice is not to move dog beds or furniture, and we agree. If your dog's bed is still comfortable, clean and in the same spot every night, leave it alone.
There are two situations where a bed has to change. The first is a bed that has flattened, so your dog is lying close to the floor. The second is a bed that cannot keep up with accidents. Cornell lists puddles "on their bed" among the signs of house soiling, and a bed that holds odor or cannot be washed becomes a nightly problem.
If you do replace it, go slowly. Place the new bed beside the old one, in the same spot, and let your dog choose when to switch. Our guide on getting an old dog to sleep on a new orthopedic bed has a step-by-step approach. Pick a calm week, not a rough stretch.
This is the situation the ZNOOZ Orthopedic Bed was built for. It is 11 inches deep, with a 7 inch high-density foam base under a 4 inch memory foam layer, made with CertiPUR-US certified foam and designed to support large and senior dogs. The cover unzips and goes in a home washing machine, so a rough night means a wash, not a replacement; our washing guide covers the steps.
A fair warning: it is a bed, not a treatment. It will not slow sundowning, and no bed will. What it can do is give an older dog firm, comfortable support in a spot that stays the same night after night, with a cover you can keep clean. If that is the problem you are solving, the ZNOOZ bed is worth a look.
Sources
All veterinary statements above come from these pages, last checked October 22, 2026. This guide paraphrases them and is not a substitute for advice from your veterinarian.
- Cognitive dysfunction syndrome, Cornell University College of Veterinary Medicine
- Senior dog dementia, Cornell University College of Veterinary Medicine (reprinted from the DogWatch newsletter)
- Cognitive Dysfunction Syndrome in Senior Dogs and Cats, VCA Animal Hospitals
