Changes of behaviour in the later stages of dementia

People in the later stages of dementia may behave out of character. These behaviours can be difficult to understand and often have different causes.

Supporting in the later stages of dementia
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Often, a change in behaviour is a form of communication. It can be a result of the person feeling a certain way (for example scared, anxious, confused or upset). This could be because they need something but are not able to tell anyone about it.

What changes in behaviour can happen in a person with dementia?


The person may react aggressively for a range of reasons. They could be in pain or feeling threatened. They may not understand what is going on, for example if a carer tries to change their clothes without explaining why.

Distress or agitation

This may be because the person is confused about where they are, who they are with or what they are meant to be doing.

Hallucinations or delusions

Some people with dementia experience hallucinations, in which they see, hear, smell, taste or feel things that are not really there. However, sometimes the person may not be hallucinating but mistaking what they have seen for something else (for example, they may see a dark rug and think it is a hole in the ground).

Others may develop delusions, where they strongly believe things that aren’t based on reality but feel real to them (for example, they may be convinced that someone is stealing from them). Talking calmly to the person, offering reassurance and meaningful activity (such as going for a walk) can help.

If you think the person is experiencing hallucinations or delusions see the GP. 


The person may repeat certain behaviours (for example, carrying out the same activity or making the same gesture over and over). This may be because they feel anxious or want comfort. Their natural interaction with their environment may have been disrupted and the behaviour is a way to make sense of what is going on.

It can help to look for meaning behind the behaviour and try to remain calm and patient.


Many people with dementia become restless and may fidget or pace up and down. They may constantly wring their hands, pull at their clothes or touch themselves inappropriately in public. This could be because of pain or discomfort, needing the toilet, a need for more physical activity or problems with their environment. It may also be because the person used to move around a lot as part of their job.

It may help to encourage exercise or activities related to interests and hobbies, both new and from their past. A rummage box, containing objects related to the person’s past such as pictures, jewellery or souvenirs, may help as it gives the person an opportunity to move their hands.


The person may become more agitated and confused in the late afternoon and early evening, which is known as 'sundowning'. This could be caused by medication or too much or too little sleep.

It may help to give the person something meaningful to do at this time of day and make sure the environment is suitable (for example, not too dark or too light). Going outside during the day (if possible) can help.

Ways to manage changes in behaviour in someone with dementia

The reasons for these types of behaviour may not always be clear. They may be due to difficulties caused by dementia (such as orientation problems), mental and physical health, habits, personality, interactions with others and the environment. It could be a combination of these things. 

Try and understand what may be causing the person’s behaviour and think about whether they have any unmet needs.

  • Ensure that any glasses or hearing aids are clean and functioning properly. Arrange regular sight and hearing checks.
  • Check whether the person’s medication is appropriate or whether they might be ill or in pain. A visit to the GP to rule out any physical problems is a good idea.
  • Check that they are not being disturbed by too many people, too much activity, loud noises, sudden movements or an uncomfortable environment (for example, one that is too hot or too bright).
  • Consider whether they may be bored or in need of stimulation. Engage the person in meaningful activities. Gentle activities such as a hand massage, listening to their favourite music or stroking a soft piece of fabric may help.
  • Make sure the person is comfortable – for example not cold, hungry, thirsty, or needing the toilet.

Weight loss and eating in the later stages of dementia

Many people with dementia lose weight in the later stages. This may be because of a loss of appetite, pain or difficulties with swallowing (dysphagia) and chewing. People with swallowing problems are at risk of choking and of food or saliva going down the windpipe, causing an infection. 

Weight loss can affect the immune system and make it harder for the person to fight infections and other illnesses. It can also increase the risk of falling and make it harder for the person to remain independent.

Helping a person with dementia who is not eating or drinking

The person should be supported to eat and drink for as long as they show an interest and can do so safely (even if they just take a mouthful or a sip). There are ways to help make this easier for the person. For example:

  • choosing a plate that is a different colour to the food (so they can see it more clearly)
  • giving the person enough time
  • putting the drink in their hand if they are struggling to see it.

Eating and drinking can still bring the person pleasure, even in the later stages. Many people’s tastes will change as they get older and as dementia progresses (for example, they might start to prefer sweet food).

Think about the person’s oral health as this will have an impact on their ability to eat and communicate (as well as helping with their general health and wellbeing). If the person has poor oral health it may lead to pain, which could mean they don’t want to eat or they behave in ways that are out of character. 

Swallowing and chewing problems can be distressing for the person and those supporting them. If the person is having difficulties, it’s important to speak to the GP – they may refer the person to a speech and language therapist or nutritional specialist. 

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