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

Diagnosing Alzheimer’s disease as early as possible 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 that you are experiencing symptoms of Alzheimer’s disease you should talk to your GP.

Alison Littleford

Getting a diagnosis was important for us so we would know what we were dealing with and could have some sense of control over it.

- Alison, whose husband Frank is living with Alzheimer's

First the doctor will:

  • Discuss your symptoms and the impact they are having on your daily life.
  • If possible, ask someone who knows you well if they have noticed any changes.
  • Check on your physical health.
  • Run a blood test to rule out other causes of your symptoms such as vitamin deficiencies or thyroid problems. They may also ask you for a urine sample.
  • Ask you to complete some quick memory and thinking tests.


If your doctor suspects Alzheimer’s or another cause of dementia, they may refer you to a memory clinic or another specialist clinic. Here, a doctor or nurse will run through some further questions and tests with you. These may include:

  • More questions about your concerns, symptoms and how they affect you.
  • A physical check-up.
  • A brain scan and lumbar puncture.
  • Completing some in-depth tests to check your memory, thinking and problem-solving skills.
Alison Littleford

Frank's diagnosis involved several visits to his GP and then to a consultant psychiatrist at the memory clinic. They needed to rule everything else out before they could give the Alzheimer's diagnosis.

Occasionally a lumbar puncture is used, where a sample of fluid is taken from the base of the spine. This tests for abnormal levels of proteins linked to Alzheimer’s disease, called amyloid and tau.

Together, these tests will help a doctor find out about the likely cause of your memory and thinking problems. Currently, there is no way to diagnose any type of dementia with complete accuracy. Your doctor will make the best judgement about the most likely cause of your symptoms based on the information they collect from these assessments and tests. They may also discuss opportunities for you to get involved in dementia research. There is more information about this on page X.

Sometimes, if someone’s symptoms are mild, they are not diagnosed with dementia but may be diagnosed with something called mild cognitive impairment (MCI). For more information about mild cognitive impairment, ask for our ‘What is Mild Cognitive Impairment?’ information. Out contact details can be found on the back of this booklet.

If symptoms are mild, a doctor may also want to wait to look for any further changes over time. For this reason, they may ask you to come back in six months or a year to repeat the assessments.

If you are assessed for dementia, you can choose not to know the diagnosis. You can choose for someone else to be told about your diagnosis instead.

The brain changes that lead to Alzheimer’s are thought to start 15-20 years before there are any symptoms. Current research is finding ways to identify and diagnose these earlier changes, and develop ways to intervene with prevention and treatment before symptoms start.

What is Alzheimer's disease?

Find out more about the symptoms and causes of Alzheimer's disease, and the treatments currently available.

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Alzheimer’s Research UK has a wide range of information about dementia. Order booklets or download them from our online form.

This information was updated in May 2024 and is due to be reviewed in May 2026. It was written by Alzheimer’s Research UK’s Information Services team with input from lay and expert reviewers. Please get in touch if you’d like a version with references or in a different format.


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