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.


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.
  • Reduced judgement,¬†for example, being unaware of danger.
  • Mood or behaviour problems such as apathy,¬†irritability, or losing confidence.


It is important to get the right diagnosis so that appropriate treatments and help can be given. If you are worried about your health or someone else’s, you should talk to your GP.

If your GP suspects dementia, you are likely to be referred to a memory clinic or specialist. You will be asked about your symptoms and medical history and may have a physical check-up.

Other tests, including brain scans and blood tests could be arranged. Very occasionally, your doctor may arrange an EEG (brain wave test) or a lumbar puncture (spinal tap) if they suspect a rare form of dementia. Together all of these things will help a doctor find out about any problems in memory or thinking and the likely cause.

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


People with mild to moderate Alzheimer’s disease could benefit from taking a cholinesterase inhibitor (ChEIs). Cholinesterase inhibitors are not a cure, but can treat some symptoms in some people.

There are three cholinesterase inhibitors licensed to treat Alzheimer’s: donepezil (Aricept), rivastigmine (Exelon) and galantamine (Reminyl). All of these drugs work in a similar way. So far, no difference in the effectiveness of the three cholinesterase inhibitors has been shown, but some people may seem to respond better to one drug than another or have fewer side effects.

People with mild to moderate Alzheimer’s may find that their condition improves by taking a cholinesterase inhibitor. This could be improvement in thinking, memory, communication or day-to-day activities. Others may find that their condition stays the same, when they would have expected to become less able with the progression of dementia. Some people may not notice any effect at all.

The most common side effects of cholinesterase inhibitors are nausea (sickness), vomiting, diarrhoea, insomnia, muscle cramp, and tiredness. These effects are often mild and usually only temporary. Not everyone will experience side effects.

Memantine (Ebixa or Axura) can help people with moderate to severe Alzheimer’s disease. Like cholinesterase inhibitors, while memantine is not a cure, it can help Alzheimer’s patients with some symptoms.

People taking memantine may find their memory, communication, thinking skills or ability to do day-to-day activities improves. Some people 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 of memantine are headaches, dizziness, drowsiness and constipation. These effects are usually only temporary.

There are also non-drug treatments which can help with the symptoms of dementia. To read more about drug and non-drug treatments for dementia, visit our general treatments section.

This information is correct as at April 2014. It is currently being reviewed through our health information production process.


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 November 2012 and is due to be updated in November 2014. If you would like a version of this information with references, please contact us.

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