Dementia with Lewy bodies

Dementia with Lewy bodies is the third most common cause of dementia.

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 doctor.

If the doctor suspects dementia, you may be referred to a memory clinic or another specialist clinic. You will be asked about your symptoms and medical history and may have a physical check-up and memory and thinking tests. You may also be sent for tests like brain scans and blood tests. Together these tests will help to identify the likely cause of the memory and thinking problems.

Brain scans such as MRI (magnetic resonance imaging) or CT (computerised tomography) can help to rule out other causes of dementia. To help make a specific diagnosis of DLB, a type of scan called a SPECT scan may be used to look for changes in the brain which are more common in this type of dementia.

DLB is closely related to Parkinson’s disease and people with Parkinson’s disease are more likely to go on to develop dementia. If dementia symptoms appear before or at the same time as people start to have movement problems, then a diagnosis of dementia with Lewy bodies is likely to be given. If movement problems are present for a year or more before signs of dementia, then a diagnosis of Parkinson’s dementia is likely to be given.

While hallucinations are common in DLB, they can also occur in conditions like Charles Bonnet syndrome, which affects people who are losing their sight. This condition is not well known, so people who have it may worry they are developing dementia. Find out more at or call 0345 051 3925.

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

This information was updated in January 2018 and is due for review in January 2020. It does not replace any advice that doctors, pharmacists or nurses may give you. Please contact us if you would like a version with references.

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