Dementia guide

Symptoms of dementia

Living with dementia

Dementia is not a disease but a collection of symptoms that result from damage to the brain. These symptoms can be caused by a number of conditions. The most common cause of dementia is Alzheimer's disease.

Common symptoms of Alzheimer's disease and other forms of dementia include:

  • memory loss, especially problems with short-term memory
  • increasing difficulties with tasks and activities that require concentration and planning
  • depression
  • changes in personality and mood
  • periods of mental confusion
  • difficulty finding the right words

Early symptoms of dementia are often mild and may get worse only very gradually. This means that the person with dementia and those around them may not notice these signs or take them seriously for some time. Also, people with dementia sometimes do not recognise that they have any symptoms.

Dementia is progressive. This means that the person's brain will become more damaged and will work less well over time, and their symptoms will tend to change and become more severe.

For this reason, it is important to talk to your GP sooner rather than later if you are worried that you may have problems with your memory.

The speed at which symptoms get worse and the way that they develop will depend on the cause of the person's dementia, their overall health and their circumstances. This means that the symptoms and experience of dementia can vary greatly from person to person.

Some people may also have more than one condition – for example, they may have Alzheimer's disease and vascular dementia at the same time.

The symptoms listed above are common in all forms of dementia. However, some types of dementia have other distinctive features. These are explained below.

Symptoms of vascular dementia

The symptoms of vascular dementia can sometimes develop suddenly and quickly get worse, although they can also develop gradually over many months. People with vascular dementia may also experience stroke-like symptoms, including muscle weakness or paralysis on one side of their body.

Find out more about vascular dementia.

Symptoms of dementia with Lewy bodies

Dementia with Lewy bodies shares many of the symptoms of Alzheimer's disease and people with the condition typically also experience the following:

  • periods of alertness and drowsiness or inactivity
  • visual hallucinations
  • times when their body 'seizes up' and they find it hard to move freely

Find out more about dementia with Lewy bodies.

Symptoms of frontotemporal dementia

Early symptoms of frontotemporal dementia typically include changes in emotion, personality and behaviour. For example, someone with this type of dementia may become less sensitive to other people’s emotions, perhaps making them seem cold and unfeeling.

They may also lose some of their inhibitions, leading to behaviour that is out of character, such as making tactless or inappropriate comments.

Some people with frontotemporal dementia also have language problems. This may include not speaking, speaking less than usual or having problems finding the right words.

Find out more about frontotemporal dementia.

Symptoms in the later stages of dementia

As dementia progresses, memory loss and difficulties with communication often become very severe. In the later stages, the person is likely to neglect their own health and require constant care and attention.

Memory symptoms in dementia

People with advanced dementia may not recognise close family and friends, they may not remember where they live or know where they are. They may find it impossible to understand simple pieces of information, carry out basic tasks or follow instructions.

Communication problems in dementia

It is common for people with dementia to have increasing difficulty speaking and they may eventually lose the ability to speak altogether. It is important to keep trying to communicate with them and to recognise and use other, non-verbal means of communication, such as expression, touch and gestures.

Read more about communication problems in dementia.

Problems with mobility in dementia

Many people with dementia gradually become less able to move about unaided and may appear increasingly clumsy when carrying out everyday tasks. Some people may eventually be unable to walk and may become bedbound.

Read more about mobility.


Bladder incontinence is common in the later stages of dementia and some people will also experience bowel incontinence.

Eating, appetite and weight loss

Loss of appetite and weight loss are also common in the later stages of dementia. It's important that people with dementia get enough help at mealtimes to ensure they get enough to eat. Many people have problems with eating or swallowing and this can lead to choking, chest infections and other problems.  

Read more about eating and nutrition.

Last reviewed: 14/02/2013

Next review due: 14/02/2015


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