Dog Dementia Symptoms: The Signs to Watch For

The main signs of dog dementia are disorientation, changes in how your dog interacts with you, disrupted sleep, accidents in the house, shifts in activity, and new anxiety. Vets group them under the acronym DISHAA. Most owners notice the night restlessness or the “getting lost” moments first, and write them off as old age. Sometimes that is all it is. But when several of these show up together and slowly get worse, it points to canine cognitive dysfunction, the medical name for dog dementia.

Here is what each sign actually looks like in a real dog, how to tell dementia apart from normal aging, and when it is time to call your vet. For the full picture of what the disease is and how it is treated, start with our guide to dog dementia.

The signs of dog dementia at a glance

• Getting “lost” or confused in familiar places, or staring at walls and corners
• Less interest in greeting you, being petted, or playing, or sudden clinginess
• Restlessness, pacing, and waking at night, then sleeping all day
• Accidents indoors from a previously house-trained dog
• Pacing, circling, or repetitive behavior that goes nowhere
• New or worse anxiety, including fear of things that never bothered them
• Forgetting commands, routines, or names they have known for years

You do not need all of these. A pattern of two or three, getting worse over weeks and months, is the signal to act.

DISHAA: the six signs, and what each one really looks like

Vets use DISHAA because dog dementia almost never shows up as one dramatic symptom. It shows up as a handful of small changes that add up.

D – Disorientation

This is the classic one. Your dog stands in the corner facing the wall and does not know how to turn around. He gets “stuck” behind furniture he has walked past a thousand times. He goes to the hinge side of the door instead of the handle side, and waits. He walks into a room and seems to forget why. Outside, he may wander to the wrong part of the yard or stand in the middle of it, lost. Early on this is occasional. Later it happens daily.

I – Interaction changes

The way your dog relates to you and to other pets shifts. Some dogs pull back: less interest in greeting you at the door, less cuddling, less play. Others go the opposite way and become newly clingy and anxious when you are out of sight. A few get irritable or snappy in ways that are out of character, which can be frightening if there are kids or other dogs in the house. Sudden aggression can be a dementia sign too, and we cover that here: can biting be a symptom of doggy dementia?

S – Sleep-wake cycle changes

This is the sign owners feel the most, because it costs everyone sleep. Dogs with dementia often flip their schedule. They sleep through the day, then pace, pant, and vocalize at night. The evening and overnight version has a name, sundowning, and it is usually the hardest part of the whole disease. We have a full plan for it here: sundowning in dogs.

H – House-soiling

A dog who was reliably house-trained for years starts having accidents indoors, with no bladder infection or other medical cause behind it. The learned connection between “I need to go” and “I go to the door” breaks down. They may even go right after coming in from outside. This is not spite or stubbornness. The wiring that managed it is failing.

A – Activity changes

Interest drops. Less enthusiasm for walks, toys, food, and the people coming home. Or you see the opposite: repetitive behaviors that lead nowhere, like pacing the same path, circling, or licking the floor. Both directions, withdrawal and repetition, point the same way.

A – Anxiety

New or worse anxiety is common. A dog who was always fine home alone develops separation distress. Sounds, surfaces, or places that never mattered now cause fear. There is a general unsettledness, a sense that your dog cannot quite get comfortable in his own life. Anxiety often tracks with the disorientation: the world stops making sense, and that is scary.

Is it dementia, or just old age?

This is the question every owner asks, and it is the right one. Slowing down with age is normal. A little more sleep, a little less spring in the step, gray on the muzzle, none of that is dementia.

The difference is in the kind of change. Normal aging is physical and gradual: stiffer joints, less stamina, duller hearing. Dementia is cognitive: confusion, lost habits, disrupted sleep, anxiety, and behavior that does not make sense for your dog. If your old dog is simply tired, that is age. If your old dog seems lost, anxious, or “not himself” in his own home, that is worth a vet visit.

One more honest point. Some of these signs can be caused by other things that are treatable, including pain from arthritis, vision or hearing loss, thyroid disease, or a urinary tract infection behind the house-soiling. That is exactly why you do not diagnose this at home.

How do I know for sure?

You confirm dog dementia with your vet, not with a checklist, because the diagnosis is partly about ruling other things out. Two things make that visit far more useful:

First, write down what you have seen. Note which DISHAA signs, how often, and when they started. A short phone video of the night pacing or the wall-staring is worth more than a paragraph of description.

Second, run our quick check before you go. It takes two minutes and gives you and your vet something concrete to work from: take the dog dementia quiz. It is a starting point, not a diagnosis.

When to call your vet

Sooner than you think. The single biggest mistake owners make with dog dementia is waiting, because the changes are easy to explain away as “he is just getting old.” Treatment works best when it starts early, while there is more function to protect. Call your vet if you notice:

• A pattern of two or more DISHAA signs getting worse over weeks
• Any sudden or fast change (that can signal something other than dementia and needs prompt attention)
• New aggression, especially around children or other pets
• House-soiling with no obvious cause

Once you have a diagnosis, there is a real plan, medication, diet, enrichment, and supplements that can slow the decline and keep your dog comfortable. We walk through all of it here: how to treat and manage dog dementia.

Frequently asked questions

This guide is educational and is not a substitute for veterinary diagnosis or care. If you are worried about your dog, talk to your veterinarian.