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5 Signs of Dog Dementia

7 min read



One of the most common things pet parents may notice is that their senior dog gets disoriented even when he’s in his normal or familiar environment.


“This often happens when the dog is out in the backyard and he goes to the wrong door or the wrong side of the door to get back in. The part of the brain that is involved with orientation has been affected.” Beaver says.


Your dog may also experience difficulty with spatial awareness. He may wander behind the couch and then realize he doesn’t know where he is or how to get out.


At bedtime you may find your dog in a different part of the house staring at the wall instead of curled up in his dog bed. Petryk says dogs have a good sense of timing, so this is a sign that something is wrong.


“The first thing you should do is to take your dog in for a check-up. It might not be a cognitive issue, so your vet may want to rule out some other possible medical causes which could involve a brain tumor or diabetes.”




Canine cognitive dysfunction can affect your dog’s interactions with people and other animals. Your once sociable dog who used to be the most popular pooch on the block now acts cranky and irritable, or even growls at other animals or children. He may lash out and bite his once favorite playmates. Petryk cautions that this behavior could be the result of something serious.


“He may be acting this way because he’s in pain. He could have arthritis or some other ailment that hurts when he moves or is touched. Your vet may want to do x-rays to rule out a painful condition.”


Some dogs withdraw from their family and their favorite activities. They may fail to notice when the doorbell rings and seem disinterested in greeting visitors, or they may stop barking at the mailman. Your dog may not even respond when you get his leash out to go for a walk.


"I've had patients whose dogs don't recognize that their favorite cookies are treats for them, “ says Petryk. “The owner's first instinct is to buy other cookies. They don't realize something else could be going on.”


Sleep-Wake Cycle Changes


A change in sleep patterns or a disruption in circadian rhythms is one of the more specific symptoms related to cognitive dysfunction. Dogs that used to sleep soundly may now pace all night. Many dogs reverse their normal schedules, so their daytime activities become their nighttime activities. This “up all night” routine can be frustrating and tiring to pet owners.


“If your dog is active at night and you want to get him to sleep, a nightlight or white noise may help him,” Beaver says.


If this doesn’t provide relief, consult your vet for medications that may ease your dog’s anxiety and reestablish normal sleep cycles.


House Soiling


Urinating or defecating in the house is one of the most common ways cognitive dysfunction is detected in dogs, especially if the dog was previously housetrained.


Petryk says that when this happens it’s important for owners to consider that their dog may have lost its ability to voluntarily control elimination or even let them know that he needs to go outside.


“After we run tests and rule out a bladder infection, kidney problems, or diabetes, then there’s usually been a cognitive change. If your dog is staring out at the sliding glass door and then poops in the house anyway and it’s not because of bowel trouble, then he’s lost the understanding that he should poop outside,” Petryk explains.


Activity Level


Dogs with cognitive dysfunction may show a decreased desire to explore and a decreased response to things, people, and sounds in their environments. They may not greet you or they may no longer respond on cue to fetch their favorite toy. They may also be less focused and show an altered response to stimuli. Some dogs have trouble eating or drinking or finding their food bowls.


"They may drop something when they’re eating and they can’t find it,” says Petryk. “If they don’t have sight or hearing issues, this can be a true indication that they are experiencing cognitive dysfunction.”


Although older dogs experience a normal decline in activity levels, they may also experience restless or repetitive locomotion.


"They may exhibit repetitive motion; things like head bobbing, leg shaking, or pacing in circles. This kind of action is more related to cognitive dysfunction or a degeneration of the brain. It’s less likely to be mistaken for anything else," Petryk says.


Owners should also be aware if their typically quiet dog now barks excessively or if he barks at times when nothing is going on.