Lewy body dementia is the second most common type of dementia after Alzheimer's disease. Protein deposits called Lewy bodies develop in nerve cells in the brain. The protein deposits affect brain regions involved in thinking, memory and movement. This condition is also known as dementia with Lewy bodies.

Lewy body dementia causes a decline in mental abilities that gradually gets worse over time. People with Lewy body dementia might see things that aren't there. This is known as visual hallucinations. They also may have changes in alertness and attention.

People with Lewy body dementia might experience Parkinson's disease symptoms. These symptoms may include rigid muscles, slow movement, trouble walking and tremors.


Lewy body dementia symptoms can include:

  • Visual hallucinations. Seeing things that aren't there, known as hallucinations, might be one of the first symptoms of Lewy body dementia. This symptom often occurs regularly. People with Lewy body dementia might see shapes, animals or people that aren't there. Hallucinations involving sounds, smells or touch are possible.
  • Movement disorders. Signs of Parkinson's disease, known as parkinsonian signs, may occur. These symptoms include slowed movement, rigid muscles, tremor or a shuffling walk. This can cause the person to fall.
  • Poor regulation of body functions. The part of the nervous system that controls automatic functions is called the autonomic nervous system. Lewy body dementia can affect how well the autonomic nervous system controls blood pressure, heart rate, sweating and digestion. This can result in sudden drops in blood pressure upon standing, dizziness, falls, loss of bladder control and bowel issues such as constipation.
  • Cognitive problems. People with Lewy body dementia might have thinking problems similar to those of Alzheimer's disease. They may include confusion, poor attention, visual-spatial problems and memory loss.
  • Trouble with sleep. People with Lewy body dementia can have rapid eye movement (REM) sleep behavior disorder. This disorder causes people to physically act out their dreams while asleep. People with REM sleep behavior disorder may punch, kick, yell or scream while sleeping.
  • Varying attention. Episodes of drowsiness, long periods of staring into space, long naps during the day or disorganized speech are possible.
  • Depression. People with Lewy body dementia might develop depression.
  • Apathy. Loss of motivation may occur.

From Mayo Clinic to your inbox

Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.


Lewy body dementia is characterized by the buildup of proteins into masses known as Lewy bodies. This protein also is associated with Parkinson's disease. People who have Lewy bodies in their brains also have the plaques and tangles associated with Alzheimer's disease.

Risk factors

A few factors seem to increase the risk of developing Lewy body dementia, including:

  • Age. People older than 60 are at greater risk.
  • Sex. Lewy body dementia affects more men than women.
  • Family history. Those who have a family member with Lewy body dementia or Parkinson's disease are at greater risk.


Lewy body dementia is progressive. This means it gradually gets worse over time. As symptoms get worse, Lewy body dementia can lead to:

  • Severe dementia.
  • Aggressive behavior.
  • Depression.
  • Increased risk of falling and injury.
  • Worsening of parkinsonian symptoms, such as tremors.
  • Death, on average about 7 to 8 years after symptoms start.

Lewy body dementia care at Mayo Clinic

June 02, 2023
  1. Lewy body dementia. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/All-Disorders/Dementia-Lewy-Bodies-Information-Page. Accessed April 26, 2023.
  2. Farlow MR. Clinical features and diagnosis of dementia with Lewy bodies. https://www.uptodate.com/contents/search. Accessed Feb. 15, 2021.
  3. Budson AE, et al. Dementia with Lewy bodies. In: Memory Loss, Alzheimer's Disease, and Dementia. 3rd ed. Elsevier; 2022. https://www.clinicalkey.com. Accessed April 26, 2023.
  4. Prasad S, et al. Recent advances in Lewy body dementia: A comprehensive review. Disease-a-Month. 2023; doi:10.1016/j.disamonth.2022.101441.
  5. Clinical management. Lewy Body Dementia Association. https://www.lbda.org/healthcare-professionals/. Accessed April 26, 2023.
  6. Understanding behavioral changes in dementia. Lewy Body Dementia Association. https://www.lbda.org/understanding-behavioral-changes-in-dementia/. Accessed Feb. 16, 2021.
  7. Taylor J-P, et al. New evidence on the management of Lewy body dementia. Lancet Neurology. 2020; doi:10.1016/S1474-4422(19)30153-X.
  8. Ferri FF. Dementia with Lewy bodies. In: Ferri's Clinical Advisor 2023. Elsevier; 2023. https://www.clinicalkey.com. Accessed April 26, 2023.
  9. Press D, et al. Management of neuropsychiatric symptoms of dementia. https://www.uptodate.com/search/contents. Accessed Feb. 15, 2021.
  10. Donaghy PC, et al. Research diagnostic criteria for mild cognitive impairment with Lewy bodies: A systematic review and meta-analysis. Alzheimer's & Dementia. 2023; doi:10.1002/alz.13105.
  11. Graff-Radford J (expert opinion). Mayo Clinic. Feb. 25, 2021.
  12. Luo G, et al. Effectiveness of non-pharmacological therapies on cognitive function in patients with dementia — A network meta-analysis of randomized controlled trials. Frontiers in Aging: Neuroscience. 2023; doi:10.3389/fnagi.2023.1131744.
  13. Liang C-S, et al. Mortality rates in Alzheimer's disease and non-Alzheimer's dementias: A systematic review and meta-analysis. The Lancet Healthy Longevity. 2021; doi:10.1016/S2666-7568(21)00140-9.
  14. Oxybutynin oral. Facts & Comparisons eAnswers. https://fco.factsandcomparisons.com. Accessed April 28, 2023.
  15. Diphenhydramine oral. Facts & Comparisons eAnswers. https://fco.factsandcomparisons.com. Accessed April 28, 2023.
  16. Cholinesterase inhibitors. Facts & Comparisons eAnswers. https://fco.factsandcomparisons.com. Accessed April 28, 2023.
  17. Huang Y, et al. Comparative risk of cardiac arrhythmias associated with acetylcholinesterase inhibitors used in treatment of dementias — A narrative review. Pharmacology Research & Perspectives. 2020; doi:10.1002/prp2.622.
  18. Choudhary G, et al. Myocardial sympathetic innervation imaging with MIBG in dementia with Lewy bodies. Journal of Nuclear Cardiology. 2021; doi:10.1007/s12350-020-02042-2.
  19. Ami TR. Allscripts EPSi. Mayo Clinic. May 17, 2023.