Why is my dog acting weird all of a sudden

Why do personality changes happen in dogs?

‘By the time your dog turns eight, he’s entering the human equivalent of the geriatric years of his life,’ Claire explains. ‘And like all older mammals, including humans, this means that his brain is less flexible and may take longer to form new associations.

‘On the one hand, this could result in him becoming a bit less competent at dealing with the world: more prone to anxiety and more aware of dangers. But it’s not all bad news – the years of training and positive situations you’ve exposed him to will also be ingrained by this stage. ‘Regardless of the type of change, though, you’ll need to keep in mind that getting older will naturally affect your dog’s behavioural and emotional development. And, as a matter of course, changes in personality are bound to come alongside that.’ Here are four common changes you might expect to see in your dog:

1. From fearful to confident

You may have noticed that your dog was prone to bouts of shyness or unexplained fear in his younger years, but now seems more secure. ‘For some dogs, this could be because he’s slowly habituated to his environment,’ Claire says. ‘It might help to think of it as the equivalent of a stay in an unfamiliar hotel. The first night you spend there is often one of broken sleep, as your brain is almost too aware of everything around you. But by the second night you’ll probably sleep much better because your mind has had a chance to work out that the strange surroundings, sounds and smells have no significance and aren’t a cause for concern.

‘Your dog is even more sensitive to stimuli such as sounds and smells, but it’s possible that, over time, he too stops responding to every new experience as a threat, as experience has taught him this is rarely the case. He’s also learned to expect certain consistencies in your behaviour, and this combination of factors gives him a secure base from which to approach the world more confidently.’

2. From docile to snappy

‘Many owners report that their once laid-back pooch has become short-tempered,’ Claire says. ‘In older dogs this is often due to muscular or skeletal problems – such as arthritis, as by the time a dog reaches the age of eight he has an 80% chance of having the condition.

‘But when your dog looks fit it’s difficult to spot that his tolerance for active play or exercise might be declining. Even though he’ll willingly go for walks, arthritis will cause him to stiffen up when he rests and he can then become grouchy, especially if disturbed. Whereas your pet may have been more tolerant of noise or younger family members when he could simply get up and walk away, it’ll now be more painful for him to do that. If he’s in discomfort, your dog’s capacity to tolerate rough and tumble will decrease, which is understandable.’

If you’ve noticed this kind of change, book a consultation with your vet. If your dog has arthritis, he could be in a lot of pain, and may need prescribed medicines to help to relieve his discomfort. But health issues like diabetes or thyroid problems will need to be ruled out too, as these can be debilitating and may also make your dog irritable and prone to aggression.

3. From energetic to lethargic

Older dogs may appear sluggish for the health reasons we’ve mentioned above, but it’s also important to be aware that age brings an increased risk of cognitive decline and conditions such as dementia for your pet. No longer being as enthusiastic to go for walks or to play – or refusing to get active altogether – can be a symptom, so it’s worth discussing anything you notice with your vet.

Also keep in mind that a dog’s sense of sight, hearing and smell lessen with age. As your dog relies so heavily on these faculties, this decline may be making him anxious. He may be retreating to avoid frightening interactions and could therefore seem ‘lazy’. However, if your dog is lethargic but also has an increased appetite, and is having more frequent nighttime accidents, these can all be signs of other health problems, such as Cushing’s disease (a condition caused by a non-cancerous tumour on the pituitary gland, which results in too much of the stress hormone cortisol being produced). Early detection can help to bring your dog’s energy and bounce back, so speak to your vet and get treatment for your pet as soon as possible.

4. From high-maintenance to mellow

Some owners notice that their once attention-seeking and territorial dog has become more placid with age. It could be the case that years of social interaction and training have made him calmer. But Claire also sounds a cautionary note: ‘Your dog may not be demanding your time as much as he once was, but that shouldn’t lead to a decrease in the amount you interact with him. Dogs are naturally sociable beings and studies show that their levels of the “happy hormone” dopamine become depleted during times when their owner is absent, and they experience real distress as a result.’ To keep your dog mentally healthy and happy, make sure you keep putting in quality time with him every day. These games can help to enrich your interactions and keep those age-related problems at bay.