Dementia in dogs

April 09, 2025

Cognitive decline, or dementia, is a disease of older dogs. Symptoms include memory loss, anxiety and confusion. It’s most common in smaller breeds. There’s no cure but medication can help to slow down the progression of the disease. Patience and supportive care will help your dog with dementia enjoy a good quality of life as long as possible.

What causes dementia in dogs?

  • Progressive disease affecting the brain, and more than simply ‘old age’.

  • The cause isn’t fully understood.

  • Dogs with dementia have abnormal proteins in their brains called beta amyloid and Tau.

  • Other health, environmental and individual factors are likely to influence how quickly the disease develops and progresses.

Is dementia more likely in some dogs?

  • The biggest risk factor for dementia is advancing age; risk increases by 50% with each year of life.

  • Having poor hearing or sight: fewer messages reach the brain to keep it occupied.

  • Neutered dogs.

  • Terrier and toy breeds are 3 times as likely as other breeds to develop dementia.

  • Dogs who don’t exercise are over 6 times more likely to be affected by dementia.

  • Dogs with other long-term illnesses: arthritis, liver disease, kidney disease, and an underactive thyroid gland.

Symptoms of dementia

  • Confusion.

  • Forgetting toilet training – accidents in the house.

  • Disorientation- getting lost in the house, staring into space.

  • Becoming less playful and more irritable.

  • Not recognising ‘familiar’ people and places.

  • Sleep/wake cycle disturbances –  awake all night, sleeping all day.

  • Pacing, barking, howling or whining.

  • Being more clingy and suffering from separation anxiety.

How is dementia diagnosed?

There isn’t a single test for dementia.

Vets diagnose dementia in dogs based on the following:

  • Changes in behaviour

  • Changes in habits

  • Physical examination

  • Ruling out other illnesses

What’s the treatment for dementia?

There isn’t a cure for dementia. The treatment goal is to improve symptoms and slow disease progression. Options include:

  • Veterinary medicines such as Selegiline, Propentofylline and anxiety medication

  • Special foods rich in antioxidants and the best nutrients for the brain

  • Supplements that support liver and brain function, or boost nerve cells

  • Vitamins and essential fatty acids

  • Complementary therapies that help with anxiety and stress (diffusers, compression shirts, massage, herbal remedies)

Living with a dog with dementia

  • Be patient. It’s hard to live with house-soiling, constant pacing, whining, sleep disturbances and separation anxiety. But negative responses, like frustration or annoyance, will only add to your dog’s stress and anxiety, and make things worse. Older dogs may not have much energy on walks but they’ll want to spend more time checking out all the interesting smells.

  • Keep to regular routines.

  • Provide more toileting opportunities.

  • Increase daytime activity.

  • Your older dog may not be able to play the same way as a puppy, but keep them interested and active, with familiar toys and games.

  • Giving your older dog a quiet area to sleep undisturbed will make life safer and more comfortable for everyone.

  • You may need to change the commands and signals you use to communicate with your dog if they have forgotten the usual ones or no longer understand them.

  • Make allowance for other illnesses.

What to expect

Dementia worsens over time and is ultimately fatal, either directly or through related illnesses. Watching a loved one decline can be heartbreaking, making you question their quality of life.

If your dog no longer has a good quality of life, euthanasia—gently ending their suffering with an anesthetic —may be the kindest choice.

Deciding when to say goodbye is incredibly difficult. The best we can do is prioritise their well-being. Ask yourself: Do the good days outweigh the bad? A quality-of-life assessment tool can help.

How to prevent dementia in dogs

Dementia is a disease of ageing and we can’t prevent it happening. The good news is that owners can do a lot to reduce the risk of early-onset dementia and slow its progression.

  • Keep your dog as active and fit as possible. Continue regular walks.

  • Keep your dog mentally active:

    • Provide games, toys and puzzle treats

    • Provide opportunity for safe supervised play with other dogs.

    • Continue to play and interact with your dog and encourage other friendly faces to do so too.

  • Keep on top of your dog’s preventive care:

    • Stay up to date with vaccinations

    • Continue with regular worming and flea treatments

    • Look after your dog’s dental health – like brushing their teeth or using dental rinses

  • Feed your dog the best diet for their age, health and lifestyle.

  • Recognise and treat other illnesses promptly:

    • Take your dog for regular check-ups with a vet

    • Give all medicines as prescribed

Is dementia contagious in dogs? Will I catch it?

Dementia affects individual dogs or people. You and your other pets are at no risk of catching dementia from your dog.

When to worry about dementia in dogs

Signs that dementia is worsening
  • Stopping eating

  • No longer interacting with you

  • Not going out for walks or toileting

  • Becoming irritable or even aggressive

  • Being unable to settle or rest

  • Suffering episodes of collapse or have seizures

Your dog may also deteriorate rapidly, either due to advanced dementia itself or when dementia happens with another illness.

 Find your nearest vet if
  • Your dog has collapsed

  • Your dog is unresponsive

  • Your dog has become dangerous to others or himself

 Joii can help with advice on
  • Medicines can help dogs with dementia

  • Games and exercise to keep your dog’s body and brain active

  • How to support a dog with poor memory and confusion

  • How to care for an anxious dog

  • If you’re worried your dog is distressed

  • To talk through options for end-of-life care

  • To talk about euthanasia and what it means

  • To find out what happens afterwards

  • With Bereavement Support

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