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5 Signs of Sundowner’s Syndrome in Dogs You Should Know

If you have a dog who is suddenly acting out of sorts, pacing at night, crying and whining, he/she may have what’s known as Sundowner’s Syndrome. The syndrome, however, isn’t a disease. It’s actually the symptom of Alzheimer’s in dogs – otherwise known as canine cognitive dysfunction syndrome.

Senior dogs, like people, can develop cognitive dysfunction as they age. It’s actually a common occurrence in dogs over the age of 9. Unfortunately, there’s no cure. There are, however, ways to supplement the brain with antioxidants and exercise to keep mental acuity for as long as possible.

This post is Sundowner’s Syndrome. You’ll learn about this one sign that is probably one of the most distressing for dog’s and dog owners alike. If you’ve been worried about your dog lately, this post might have some answers for you.

Sign 1: Restless Dog Syndrome

You know your dog better than anybody else. Cognitive dysfunction in dogs tends to cause some confusion during the day, but when the sun goes down a whole new phenomena develops.

People have reported episodes of Sundowner’s Syndrome where the dog whines and cries all night, pants heavily, paces the floor, remains restless and spend the night poking his/her owners.

Sign 2: Dog is Suddenly Afraid of Everything

Fear in dogs can occur for all kinds of reasons. It’s not necessarily a sign of cognitive dysfunction or sundowner’s syndrome in dogs. If a new animal has recently been introduced into the home, the dog is in a kennel or with an unknown dog sitter, or their are fireworks over the night sky, it’s natural that your dog could be experiencing fear.

However, without any obvious fear factors around, an aging dog could be showing early signs of sundowner’s syndrome related to Alzheimer’s in dogs.

sundowner's syndrome in dogs can cause confusion, howling, whining, and fear at night
barking dog

Fear in dogs might not actually look like fear. Watch for:

  • Tail tucked between legs
  • A lot of yawning
  • Hair (hackles) raised across the back or neck.
  • Avoiding eye contact
  • Whale eye
  • Lip licking
  • Sudden, intense itching where he/she wasn’t previously itchy

Sign 3: Nighttime Distress

A lot of symptoms like using the bathroom in the house, bumping into walls, getting stuck in corners, and suddenly losing interest in previously fun things can happen day or night. These are all signs of Alzheimer’s in dogs (or canine cognitive dysfunction).

Sundowner’s syndrome in dogs refers to the activities and behaviours that happen in the night when everyone has gone to bed.

The gradual loss of cognitive function is terrifying. The dog doesn’t know what’s happening. All he/she knows is that it’s dark and he can’t recognize familiar things, may not recognize the room where his/her owner’s sleep, etc.

As a result of this disorientation, the dog will become very scared and may pace, whine, howl, or cry.

Sign 4: Aggression and Irritability

It could be said that all of the signs noted above are directly related to the fear and confusion a dog with dementia feels. People with Alzheimer’s Disease and other types of dementia often suffer the same symptoms.

Anger and hostility can also show itself in the wee hours of the evening. Your otherwise happy dog may suddenly bark, snarl, or growl.

Other animals in the house should be kept apart from the dog with dementia for safety reasons. You still have the same loyal dog you always have; but now he/she is sick and can’t help it.

Sign 5: Destruction of Property

Imagine the confusion and fear a dog with dementia must experience. Every dog may have a different experience with Sundowner’s Syndrome. Some will just cry at night and others may turn to destruction.

Fear and agitation can lead to obsessive chewing and destruction of shoes, books, wallets, etc. This process might even remind you of the puppy stage when your dog had to be crated temporarily to avoid chaos in the house.

The #1 Brain Protective Blend of Food for Sundowner’s Syndrome in Dogs

A study published in the British Journal of Nutrition (volume 119, issue 3, pp 349-358) shows how administration of super foods can improve cognition in senior dogs.

A controlled study of 147 dogs between the ages of 9 and 11 years old were divided into groups. One group received a diet of nutrient dense food containing antioxidants, B Vitamins, fish oil, and L-arginine. (an amino acid).  Before the study began, each dog was assessed for baseline cognition.

The study continued for six months, and at the end of that period it was determined that the group of dogs who’d been fed the nutrient dense diet had significantly improved cognitive ability.

There is no cure for dementia in dogs, but there’s no question that this particular blend of antioxidants and vitamins aided the dogs in a meaningful way.

Signs of Sundowner’s Syndrome in Dogs

If we lived in a perfect world my dogs would not get old, and neither would I.  The reality is, we’re all aging day by day, including our dogs.  I have two dogs aged 6 1/2 years old and 7 years old. So far, they are both healthy and dementia free. 

I have a 17-year-old cat, however, who often finds himself staring at walls or getting lost in the house.  Sundowner’s Syndrome is a term used to describe a specific behavior demonstrated in people with Alzheimer’s who become restless and belligerent in the evening.

Sundowner’s Syndrome in dogs is very similar, except it involves the dog panting and pacing the floor all night. He/she might howl, bark, or whine. You might get nudged in the night by your restless, confused dog.  Suddenly, your dog might appear to be acting out by voiding on the floor or becoming aggressive after a lifetime of calmness. Anxiety is also a common sign of dementia (cognitive dysfunction syndrome) in dogs.

Hard to Diagnose – Safe to Treat

If you present to your veterinarian questions about sundowner’s syndrome in dogs, specifically the symptoms your dog has been showing, he or she will want to rule out all other probabilities first. Diagnosing canine cognitive dysfunction is often a process of elimination.

Night Crating

Night crating is something you want to do with caution. If you’re able, bring the crate into your bedroom at night. Have your dog spend a few hours with a simple toy or a blanket and then use those items in the crate rather than switching them up for something else. Don’t overload the crate, just keep it simple and comfortable.

If your dog won’t go in the crate, try keeping your dog in your bedroom with the door closed. Leave the crate door open as an invitation. It’s very likely that your dog is still going to pace and whine, but without free roam of the house, he/she may settle into the crate for “protection”.


People want quality dog foods that are relatively inexpensive and easy to buy.  The pet food industry is listening and, as a result, is releasing new brands formulated with antioxidants and free from additives and fillers.

These days there are many great products on the market that veterinarians highly recommend. If your dog has special dietary needs, you may need to work with the veterinarian to come up with a good diet that includes antioxidants. Otherwise, you can try the following dry food diets and supplements. Remember that they don’t work overnight. In order to see a change in your dog’s mental awareness, you may need to use these products continuously over several weeks.

Hills Science b/d Dry Dog Food

Look for Hills Science products that are formulated for senior or geriatric dogs. The food should include a fair amount of antioxidants.


Other Recommended Supplements for Dogs with Sundowner’s Syndrome:


There are two different types of exercise that dogs with dementia can benefit from:

Puzzles/Food Puzzles

Puzzles like the one in the image below are designed to make your dog think. He/she is forced to use the natural gifts and senses to find the food.

Physical Exercise

Dogs with dementia often don’t want to do the things they normally did. Playing ball, going for a run in the park, swimming, etc. However, the more you can get your dog to do the better. Exercise helps keep the mind young longer.

The dog treadmill in the image below might be a bit much; however, click on the link to find a wide variety of other ideas and games to play with your dog.


At the end of the day, we want our dogs to have a great quality of life. Whether your dog has Sundowner’s Syndrome or some other illness that is affecting him or her, remember that there are still a lot of things you can do to keep your dog happy.

Exercise, patience, supplements, and follow-up visits with the veterinarian are all highly recommended treatments for Sundowner’s Syndrome in dogs.

I wish you luck and ask that you contact me at: [email protected] with tales of your dog’s triumphs.

Thank you for reading this post. I hope you were able to get useful information.

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