Alzheimer's Research UK


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Alzheimer’s Disease

Alzheimer’s is a disease that causes dementia. It is probably the best-known cause of dementia, accounting for about two-thirds of cases in the elderly. Around 500,000 people in the UK have Alzheimer’s. This information aims to give an introduction to Alzheimer’s, by providing an overview of the causes, symptoms and treatments. We hope you will find it helpful.


Alzheimer’s often develops slowly over several years. It is not always obvious to begin with and symptoms can overlap with other illnesses. Sometimes it can be difficult to distinguish Alzheimer’s from mild forgetfulness which can be seen in normal ageing.

Everyone with Alzheimer’s will experience symptoms in their own way. Early signs usually include difficulties forming new memories, but people may also experience language or spatial awareness difficulties.

Typical early symptoms of Alzheimer’s include:

  • Regularly forgetting recent events, names and faces.
  • Regularly misplacing items or putting them in odd places.
  • Confusion about the time of day.
  • Disorientation, especially away from your normal surroundings.
  • Getting lost.
  • Problems finding the right words.
  • Mood or behaviour problems such as apathy, irritability, or losing confidence.

Alzheimer’s gets worse over time, but the speed of change varies from person to person.
As Alzheimer’s progresses:

  • People will find that their ability to remember, think and make decisions worsens.
  • Communication and language become more difficult.
  • A person’s behaviour may change and some people can become sad or depressed.
  • Anxieties or phobias are quite common.
  • People may experience hallucinations, where they may see things or people that aren’t there.
  • Problems with sleeping and restlessness at night often occur.
  • Anger or agitation become more common.
  • People may become increasingly unsteady on their feet and fall more often.
  • People gradually require more help with daily activities like dressing, toileting and eating.


Diagnosing Alzheimer’s is important. It means you can get the right support and treatments. It also means you can plan for the future.

If you are worried about your health or someone else’s, you should talk to your GP. If your GP suspects dementia, they may refer you to a memory clinic or another specialist clinic. Here, a doctor or nurse may run through some questions and tests with you. These are likely to include:

  • Asking you some questions about your symptoms and medical history.
  • Asking about your mood.
  • Speaking with your partner or someone close to you about your symptoms.
  • Having a physical check-up.
  • Completing some standard pen-and-paper tests to check your memory, language and problem-solving skills.

These tests may be repeated, perhaps every six to 12 months, to see if there are any changes. Sometimes, if symptoms are mild, looking for change with time is the best way to be sure if anything is wrong.

You may also be asked to undergo other tests, including brain scans and blood tests. Together all of these things will help a doctor find out about any problems in memory or thinking and the likely cause.

If you are assessed for the possibility of having Alzheimer’s or another form of dementia, you can choose not to know the diagnosis. You can also choose who else can know about your diagnosis.

If you are given a diagnosis of Alzheimer’s, you may be offered various types of support. You may also be prescribed drugs or other treatments to help with symptoms or improve your quality of life.

For more general information about diagnosis of dementia visit our diagnosis page.


There are several treatments available to help with the symptoms of Alzheimer’s.

Non-drug treatments

Cognitive stimulation activities are designed to stimulate thinking skills and engage people who have Alzheimer’s. They are often group-based and include games, with an emphasis on enjoyment. The benefits of cognitive stimulation for people with Alzheimer’s could include improvement in memory, thinking skills and quality of life.

People with mild to moderate dementia, including Alzheimer’s, should be given the opportunity to participate in cognitive stimulation programmes, if available. You can discuss your options with your doctor.

Drug treatments - Cholinesterase inhibitors

People with mild to moderate Alzheimer’s disease could benefit from taking a cholinesterase inhibitor. These drugs work by increasing the amount of a chemical called acetylcholine which helps messages to travel around the brain. Cholinesterase inhibitors do not prevent the disease from progressing, but may help people to function at a slightly higher level than they would do without the drug.

There are three cholinesterase inhibitors to treat Alzheimer’s:

  • donepezil (Aricept)
  • rivastigmine (Exelon)
  • galantamine (Reminyl)

These are available on NHS prescription for people with mild and moderate stage Alzheimer’s.

Some people with Alzheimer’s find that their condition improves by taking a cholinesterase inhibitor. This may include improvement in thinking, memory, communication or day-to-day activities. Others may not notice an effect.

Some people have side effects from these drugs. The most common are feeling sick, vomiting, diarrhoea, being unable to sleep, muscle cramp and tiredness. These effects are often mild and usually don’t last long. Not everyone will have side effects.

Drug treatment – Memantine

Memantine (Ebixa or Axura) is recommended for people with severe Alzheimer’s disease, and for people with moderate Alzheimer’s if cholinesterase inhibitors don’t help or are not suitable. Memantine does not stop the disease from progressing but can help with some symptoms.

Some people taking memantine may not notice any effect at all. Others may find that their condition stays the same, when they would have expected it to decline. Some people experience side effects when taking memantine. The most common side effects are headaches, dizziness, drowsiness and constipation. These are usually short-term effects.

Treatments for depression, agitation, anxiety and aggression

People with depression or anxiety in Alzheimer’s may be offered social support or psychological treatments, such as cognitive behavioural therapy (CBT), to help with symptoms. CBT provides an opportunity for people to talk about their concerns with a specialist, and aims to help people develop different ways of thinking and behaving. People with more severe symptoms may also be offered an antidepressant drug, although these are not always suitable for someone with Alzheimer’s. Your doctor will carefully consider what may be appropriate.

To help relieve symptoms of agitation and aggression a doctor should review someone’s physical and mental health and environment. This helps to identify any causes or triggers which could be removed. Approaches such as aromatherapy or music therapy may also be considered. This is likely to depend on your preference as well as the availability of treatments.

In some circumstances antipsychotic drugs such as risperidone (Risperdal) may be used to relieve very severe symptoms. These drugs are not suitable for everyone and your doctor will carefully consider what is appropriate. These drugs can have serious side effects and their use should be carefully monitored.


There are a number of organisations that can provide help and support to people with Alzheimer’s, their families and carers. For contact details, visit our caring for someone with dementia page.

Early-onset Alzheimers

Although often thought of as a disease of the elderly, around 4% of people with Alzheimer’s are under 65. This is called early-onset or young-onset Alzheimer’s. It usually affects people in their 40s, 50s and 60s.

If you are worried about yourself or someone else who is showing symptoms of dementia, talk to your GP. They will be able to rule out other health issues such as depression or anxiety which may cause similar symptoms in younger people. They will also be able to refer you to a specialist for other tests if necessary.

While some symptoms can be similar to those of late-onset Alzheimer’s, the disease can also reveal itself in more unusual ways in younger people. This can make it more difficult for people, families and doctors to recognise.

Symptoms of early-onset Alzheimer's can include:

  • Memory problems which interfere with everyday life. This may include forgetting messages or recent events which would normally be remembered, or repeating questions.
  • Confusion or disorientation. People may become confused in unfamiliar situations and lose a sense of place and time.
  • Changes in personality and behaviour. These may be subtle at first and could include apathy, depression or loss of confidence.
  • Language problems - difficulty finding the right words and communicating. This may sometimes be called ‘progressive aphasia’.
  • Visual problems – people can have difficulty recognising words and objects and judging speed or distance. When visual problems are a major symptom, the disease may be called ‘posterior cortical atrophy’.

Alzheimer’s is a progressive disease, which means that symptoms get worse over time.

The impact of early-onset Alzheimer’s can be significant – people are often working and may have young families. For details of organisations that can offer support and advice, visit the caring for someone with dementia section of our website. You can also ask your doctor.

Can I inherit early-onset Alzheimer’s?
In most cases the answer is no. Inherited or ‘familial’ forms of Alzheimer’s are rare.

Several genes have been identified that play a role in the development of rare familial Alzheimer’s. Mistakes in these genes (called mutations) can cause a build-up of a toxic protein called amyloid in the brain. If someone has a strong family history of Alzheimer’s at a young age, genetic testing may be suggested and genetic counselling may be offered to close relatives.

In the vast majority of cases, the cause is still unclear. It is likely to be a combination of our age, lifestyle, environment and genetic make-up.

Will early-onset Alzheimer’s progress faster?
It is difficult to know. There is some evidence that early-onset Alzheimer’s may progress faster and more aggressively, but experts are unsure whether this is conclusive. Every person’s experience is different and there can be a huge amount of variability in people’s response to the disease. Difficulties with diagnosis may mean that people are diagnosed later, making their progression seem faster. Research into better methods of detection will help to improve early diagnosis.

Is there research underway to learn more about early-onset Alzheimer’s?
There is still a lot to learn about early-onset Alzheimer’s. Alzheimer’s Research UK has funded over £2.8 million of pioneering research into early-onset Alzheimer’s. We fund research across the UK. Several studies are looking at the genetics of early-onset Alzheimer’s. Another is working with people with early-onset Alzheimer’s to follow their health over several years. Our studies are helping to increase understanding of the condition, improve diagnosis and develop potential new treatments.

This information was written in March 2014 and is due to be updated in March 2016.


There is still a lot to learn about what causes Alzheimer's. Scientists know that during Alzheimer’s two abnormal proteins build in the brain. They form clumps called either ‘plaques’ or ‘tangles’. These plaques and tangles interfere with how brain cells work and communicate with each other. The plaques are usually first seen in the area of the brain that makes new memories. A lot of research is focused on finding ways to stop these proteins in their tracks and protect brain cells from harm.

Risk Factors

Alzheimer’s and other dementias are complex diseases. We are making considerable progress in understanding how they develop and it’s clear that they don’t have one single cause. It is likely that a mixture of our age, genes, environment and lifestyle could contribute to whether we develop Alzheimer’s.

The risk of developing Alzheimer’s increases with age. That means as we get older, we are more likely to develop it. We can’t change our age and there is currently no way we can completely prevent dementia but research suggests there may be some simple things we can all do that might help lower our risk. To read more about these, visit our section on risk factors and prevention.


Alzheimer’s Research UK is currently funding pioneering projects into causes, preventions and treatments for Alzheimer’s. To read more about the studies we fund, visit our projects page.

Unless otherwise stated, this information was written in April 2014 and is due to be updated in April 2016. If you would like a version of this information with references, please contact us.

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