Changes in behaviour

Dementia can affect a person’s behaviour. There can be many reasons for a change in behaviour including changes taking place in the brain, being in pain, change in routine, reduced capacity to communicate their needs or feeling misunderstood and not listened to.

You may sometimes find your loved ones behaviour confusing, irritating or even upsetting. It can be difficult to know what to do or how to respond.


Remember, your loved one is not being difficult...They can't help their behaviour


Understanding dementia and the impact it can have on a person’s behaviour can help. The person may be in pain or discomfort – they may be constipated or thirsty, or in pain from an infection such as a urinary tract infection (UTI) which can cause great distress. Sitting or lying in one position and uncomfortable or tight clothes can lead to pressure sores. Other causes of pain include arthritis, headaches, foot problems, dental pain and osteoporosis. There are people who can help you to do this.

Always discuss concerns about behaviour changes with your GP or consultant, who will be able to check whether there is a physical illness or discomfort present and provide some advice. They will help you to understand the behaviour and explore ways to help to deal with it. In some cases, there may be medications that can help to alleviate some symptoms. In other cases, there may be a reason for the behaviour such as an undiagnosed infection which could be causing pain or discomfort.

Enjoy the time with your loved one and keep a sense of humour - it lightens some difficult situations!

Judy, Dublin.

Changes in behaviour during COVID-19

The current COVID-19 outbreak means many of our usual routines have been disrupted which may affect behaviours in a person with dementia. There are things that you and the person with dementia can do to help them to meet their needs and reduce the risk of changes in behaviour. For example:

  • Short simple sentences when explaining COVID-19 and why certain services are closed.
  • Answer their questions using their words.
  • Speak in a calm clear voice.
  • Maintain a structured daily routine and activities.
  • Limit listening to news bulletins. Hearing about the pandemic repeatedly can be upsetting.
  • Try to remain calm, try not to raise the alarm about the virus to the person you care for and limit what you say about COVID-19.
  • Daily walks outside when possible.
  • Gentle exercises at home.

Even though a person with dementia may have difficulties with their memory, they still retain emotions. This means they are more likely to respond to the emotional aspects of a situation. It’s important to think about how they are feeling, what they are trying to express, and how to support their emotions. It may help to validate the person’s feelings for example ‘I can see that this is difficult for you’.

To read more download our factsheet – Practical tips for changes in behaviour

It is also important for you to look after yourself as everyone caring for someone with dementia needs support and people with whom they can discuss their problems and feelings.

Talking to someone can help. Bottling up your feelings, or not taking the time to address them, is likely to make things worse. You can to speak in confidence to our Helpline by calling 1800 341 341, email or via Live Chat at

You can also visit our webpage for carers on Looking after yourself for more practical tips.

It is important that the doctor working with you and your loved one knows about behaviours that emerge and works with you and your loved one to understand and deal with them.

Our fact sheets will help you to understand and cope with some of the behaviours that can emerge when a person has dementia. Not every person with dementia will experience all these behaviours, choose the ones that you feel are relevant to you.

Read and download our factsheet:

If you would like printed copies of these factsheets contact our national Helpline at 1800 341 341 or email We post copies free of charge to family members and friends of people with dementia.

This video explains how parts of the brain can become damaged, and this can result in changes in behaviours that may be difficult to understand and deal with.

Unusual Behaviour

Each person with dementia is an individual with different needs so there is no best way of dealing with a particular behaviour. It may help to try out a number of approaches if the person is unable to tell you how they are feeling. Ask for advice from professionals or other carers before you become too stressed.

Try to remember that the person you are caring for is not being deliberately difficult, and make sure you have support for yourself and having someone to talk to.

There are a number of unusual behaviours that may occur as the dementia progresses including:

Repeating information or questions

The person may not remember asking a question or discussing a particular topic previously. This is due to their short term memory being affected. The person may become anxious about future events and ask questions repeatedly. If this is the case it may be more beneficial to tell the person closer to the event e.g. that you will be going to the shops in 10 minutes. This means they will have less time to worry

Tips for carers:

  • Try to be tactful when answering – Don’t say ‘ I have just told you that’ as it will increase feelings of anxiety and confusion
  • Try to get them to remember and answer for themselves if possible. For example if they ask if it is lunch time respond with ‘Have you looked at the clock?’ Or if they ask do we need more milk respond with ‘Why don’t you have a look in the fridge to see?’
  • Try to distract them with an activity
  • Make an excuse to leave the room for a while if you cannot contain your irritation

Repetitive movements

You may find the person seems to constantly be doing the same thing such as packing or unpacking a bag or rearranging furniture in a room

Tips for carers:

  • The behaviour may relate to a former activity such as travelling, organising an office or entertaining. If you can work out what this activity might be it may help you understand better why the person is repeating the movement and may also serve as a basis for conversation
  • The person may be bored and may need more stimulating activities or more contact with people.

Una: Dealing with Repetition

Trailing and checking

The person may constantly follow you or want to know where you are going. Loss of a sense of time may mean that a few movements may seem like hours and they may feel safest by your side

  • Try to stay calm and not speak sharply as this will only increase anxiety
  • Try to make sure you have some time to yourself throughout the day
  • Provide the person with an activity. Sometimes a pet or a familiar activity can be reassuring
  • It may be reassuring if the person can hear you sing or have the radio on in the background if you are in another room

Shouting and screaming

The person may continuously call out for someone or shout the same word, scream or wail. There are several possible reasons for this including being in pain, hallucinating, distressed, anxious, attempts to communicate a need e.g. being hungry or being bored. It may even be because there is too much noise around them or it may be as a result of damage to the brain due to the dementia.

Tips for carer:

  • Try to figure out what triggers this behaviour. Perhaps keep a diary to help you identify the circumstances in which the behaviour occurs
  • Speak slowly in a calm and reassuring voice

Laughing and crying

The person with dementia may laugh or cry uncontrollably for no apparent reason. This may be associated with hallucinations or delusions or it may be due to the effects of brain damage. It is especially common in people with vascular dementia.

Lack of inhibition

The person may be rude or behave in ways that are socially inappropriate which can cause others to be embarrassed or distressed. The reason for a lack of inhibition may be because of specific damage to the brain, an event triggering the behaviour, sexual frustration, being too hot or cold or needing the toilet. Examples include undressing or being naked in public, lifting up a skirt or fiddling with flies on a pants, touching their genitals, insulting someone or swearing.

Tips for carer:

  • React to the person in a calm, gentle voice and try to understand their reason for the behaviour
  • Advise them the behaviour is inappropriate and try to distract the person with an activity
  • Be aware of certain triggers – perhaps the behaviour only happens in crowded places where it is noisy and they are confused.
  • It may help to explain the person’s condition to others so they understand why the person is behaving this way.

Pacing and wandering

The person may pace up and down within a room or wander around outside which can become quite distressing and worrisome for the family of a person with dementia. There are a number of reasons as to why someone may act in this behaviour including being hungry or thirsty, bored, angry, distressed or anxious, remembering an old memory or place,

Tips for carer:

  • Check with the doctor if the medication could be interfering with the persons sleep pattern or confusing them further
  • Ensure the person always carries a form of ID which includes their name and address. Why not get a copy of our Helpcard which is for people with dementia who may need support when out and about.
  • Identify the time of the day the person is likely to wander and plan activities around that time.
  • Consider putting buzzers or bells on the door to notify you when the door opens and closes
  • If the person does wander it is important to stay calm, check the usual places the person may visit, notify neighbours, contact the local Gardaí and advise them what the person is wearing and advise them of the persons medical condition

Martin: Dealing with wandering

Hiding or losing items

The person with dementia may deliberately hide objects to keep them safe and then forget where they are or that they have the items. They may also become paranoid and believe the items will be stolen or taken if they do not hide them

Tips for carers:

  • Make sure you do not leave important documents or valuables lying around
  • Try to find out the persons hiding place so that you can tactfully help them find the missing items
  • Keep a spare set of keys somewhere safe
  • Consider getting an item finder device to help you find items. More information is available in the Practical steps to support your independence resource


People with dementia may become suspicious and worry that other people are taking advantage of them or out to harm them in some way. For example, they may accuse someone of stealing from them when they mislay an object or image that a friendly neighbour is plotting against them.

The reason behind suspicion may be due to failing memory or an inability to recognise people they know or not being able to make sense of what is happening around them.

Tips for carers:

  • Avoid arguing with the person and stay calm as what they are feeling is real to them. Listen to what they are saying and reassure them.
  • Do not automatically dismiss the person’s suspicions. Investigate any suspicions that could potentially be true.
  • Explain to others in contact with the person that any unfound accusations are as a result of the dementia and that they should not take them personally.

Aggressive behaviour

  • . Speak in a reassuring voice and attempt to distract their attention or leave the room if necessary.
  • Try not to show any anxiety as this may increase the person’s agitation.
  • If they are physically violent, give them plenty of space. Closing in or trying to restrain the person, unless absolutely necessary, can make matters worse. You may need to leave them until they have calmed down or call for help.
  • Try to distract the person with another activity or subject


  • Do not try to punish the person. They are unable to learn from experience in this way and will probably forget the incident very quickly. Try to behave as normally and reassuringly as possible.
  • If aggressive incidents are frequent or worrying, discuss them with a professional such a psychogeriatrician, community psychiatric nurse or public health nurse. They may be able to offer support and suggest other ways of handling the situation.
  • Generally, it is best to avoid treating aggressive behaviour with drugs as these can add to confusion. However, if it does seem that such drugs are unavoidable the doctor will want to prescribe the minimum effective dose and to review the treatment regularly.

Your own feelings

It is important to remember that, although much of the aggression may be directed at you, it is not intentional but simply because you are there. However, any incident will probably leave you feeling quite shaky. A cup of tea with a neighbour, a phone call to a friend or a little time spent quietly on your own will help you recoup your resources.

Don’t feel guilty if you do lose your temper. You are under great stress. If aggressive incidents are frequent or worrying discuss them with a professional such as your GP, public health nurse or a Dementia Adviser. They may be able to offer support and suggest other ways of handling the situation. Don’t bottle up your feelings or resentments. Talking things over with a friend, a professional or within a carer’s support group may help.

Hallucinations and Delusions

Some people with dementia may experience hallucinations or a delusion which is when someone may see, hear, smell, taste or feel things which are not really there. Of course not everyone with dementia will be affected and not everyone who has these problems has dementia. The following looks at ways of handling these experiences.

  • The person may realise their mind is playing tricks on them and may ignore the hallucination
  • The person may find it difficult to assess whether the hallucination is real or not. In such instances they may find it reassuring if you go with them to confirm that nothing is there.
  • As the dementia becomes more severe, some people may become convinced that what they are seeing or hearing is real. This can be very frightening. It is worth trying to let them know that, although you cannot share their experience, you do understand that it is distressing for them. Try to distract them. There is no point in arguing about whether or not what they are seeing is real.
  • Hallucinations are less likely to occur when the person is occupied or interested in what is going on around them.

If the person with dementia is distressed by their hallucinations or if the hallucinations persist, speak to the GP as medication can sometimes help.

Visual hallucinations

Visual hallucinations are the most common type of hallucination in dementia. The person may see people, animals or other objects. Sometimes the hallucinations involve quite complicated scenes or bizarre situations.

Visual hallucinations can start with misinterpretations. The person may think they see faces or objects in swirling patterns on fabrics or in the shadows in a room, for instance.

Many people with dementia who experience visual hallucinations only experience them occasionally. Moreover, they often only last a few seconds. However, sometimes they are more persistent and troublesome.

Possible causes of visual hallucinations include:

Illness: Hallucinations can result from physical illness such as infections or the side-effects of some types of medication. Advice from a GP is usually necessary to help rule out these possibilities.

Eyesight: Visual hallucinations may be due to poor eyesight. Poor eyesight cannot always be improved but you should:

  • arrange regular eye checks and encourage the person to wear their glasses if they need them
  • check that any glasses worn are clean and the prescription is correct
  • discuss with the GP whether cataracts should be removed if affecting vision
  • make sure there is good lighting in the room.

Changes in the brain: People sometimes experience hallucinations because of changes that are occurring in their brain as the dementia progresses.

Visual hallucinations often occur in people who have Lewy Body dementia. With this type of dementia, the person usually has a mixture of the symptoms found with Alzheimer’s and Parkinson’s disease.

People with this form of dementia are more likely to have persistent visual hallucinations together with stiffness and slowing of movement and marked fluctuations in their abilities. If this is the case, antipsychotic medication, which is sometimes used for the treatment of troublesome hallucinations, can make stiffness worse. It should, therefore only be prescribed in low doses, if at all, and regularly reviewed.

Auditory hallucinations

Auditory hallucinations occur when people hear voices or other noises although nothing is there. As with visual hallucinations it is important to rule out possible causes such as physical illness and the side-effects of medication. It is also worth checking the person’s hearing and making sure their hearing aid is working properly, if they wear one.

One sign that the person may be having hallucinations involving a voice is when they talk to themselves and pause, as though waiting for someone else to finish what they are saying, before continuing. However, it is important to remember that not everyone who talks to themselves is having hallucinations.

Shouting at people who are not there also suggests the possibility of hallucinations.

People are less likely to hear imaginary sounds while they are talking to someone real so company can help.


People with dementia may sometimes become rather suspicious, usually due to their failing memory. They may accuse someone of stealing from them, when something has been mislaid for example.

However, they are often reassured when the object is found.

With some people this suspicion goes much further and they may develop distorted ideas about what is actually happening. They may become convinced that other people want to harm them, for example, and no amount of evidence to the contrary will persuade them otherwise. This kind of belief is called a delusion and can be very distressing both for the person with dementia and for those close to them.

People with dementia usually have odd ideas because of the changes that are occurring in their brain. However, sometimes these ideas may also follow on from hallucinations. There is often little point in arguing with the person as this only cause’s further distress.

  • Try to reassure the person that you are on their side and want to help them.
  • Distract them with other activities.
  • Ask for advice from a public health nurse
  • Medication can sometimes be helpful, particularly if the person is becoming aggressive. Ask the GP.

Explaining behaviour

It is important to explain any unusual beliefs or behaviour to all those in contact with the person with dementia so that they understand the situation and can reassure or distract the person where appropriate.

Sexual difficulties

If you are caring for a partner with dementia there will be many changes in your relationship over time and these may include changes in your sexual relationship. Of course, every couple and each situation is different but sexual problems, when they occur, can often be a cause of great distress.

You are likely to experience a sense of loss if a good sexual relationship ceases or no longer becomes enjoyable. It may help if you can express your feelings to a professional or a good friend rather than bottling your feelings  up. If you are part of a carers group you could raise the issue at the next meeting to see how others in a similar situation have dealt with it. It is important to remember that any strange or uncharacteristic sexual behaviour is likely to be part of the dementia and not directed at you in any personal way.

Of course, this may not be an area of concern for you at present. You may be able to continue with a satisfying sexual relationship for quite a few years to come or you may feel happy that you can remain affectionate and close in other ways.

Before the diagnosis

You may become aware of rather puzzling changes in the period before dementia is diagnosed.

Perhaps your partner has become less interested in sex and you feel hurt or rejected, or perhaps they have become more sexually active but less loving and considerate.

With a diagnosis of dementia you can at least feel assured that nothing personal is involved and perhaps make allowances for changed behaviour. It may help to talk to your GP or other professionals about why the dementia affects your partner’s sexual behaviour in a particular way.

Diminishing sexual interest

Many people with dementia do seem to lose interest in a sexual relationship and the person may become quite withdrawn at a fairly early stage. Being stroked or cuddled may give them reassurance, but they may not be able to initiate any affection themselves.

Increased sexual demands

You may find that your partner’s desire for sex has increased, sometimes resulting in quite unreasonable and exhausting demands, often at odd times or in inappropriate places. This may make it difficult for you to show normal affection in case your partner mistakes it for a sexual advance.

Carers’ reactions

Carers describe a wide range of feelings about continuing a sexual relationship with their partner, ranging from pleasure that this is something which they can still share to distaste at being touched by someone who seems like a stranger. As the illness progresses, the situation often changes and so do their feelings.

  • Some carers find it impossible to contemplate sex because they are caring for their partner as a parent might for a child. They find that intimate tasks they have to do for the person put them off the idea of sex.
  • Many carers find it hard to enjoy a sexual relationship when so many other aspects of the relationship have changed and little else is shared. They feel they are living with a different person.
  • Some carers find that their partners are clumsy and inconsiderate due to the dementia, but they don’t want to undermine their confidence. Sex becomes something to be endured rather than enjoyed.

Carers often feel guilty about their reactions and feel the need to talk to someone who understands the situation.

For further information:

If you would like printed copies of these factsheets contact our national Helpline at 1800 341 341 or email We post copies free of charge to family members and friends of people with dementia.

Need help?
Call the National Helpline
Back To Top