by EBSCO Medical Review Board
NMDA Receptor Antibody Encephalitis; Anti-NMDA Receptor Antibody Encephalitis; Autoimmune Encephalitis; Neuroautoimmune Encephalitis; Autoimmune Synaptic Protein Encephalopathy Syndrome (ASPES)


Anti-NMDA encephalitis is a problem with the immune system. It causes the body to make antibodies that attack proteins called NMDA receptors in the brain. This causes the brain to swell and not work as it should. It is rare.


The exact cause is not known. It may be a mix of genetics and the environment.

Risk Factors

This problem is more common in women. It is also more common in young adults and people under 45 years of age.


The disease starts off slow and get worse over time. Problems may be:

  • Flu-like problems
  • Problems sleeping
  • Problems with memory and thinking
  • Problems with speaking and movement
  • Seizures
  • Changes in behavior, such as irritability, seeing things that are not real, or believing things that cannot be true
  • Loss of consciousness


The doctor will ask about your symptoms and health history. An exam will be done.

These tests will be done to look for signs of the antibodies:


The goal is to stop the antibodies from attacking. This may be done with:

  • Steroids to lower the level of antibodies
  • IV immunoglobulin of healthy antibodies from a blood donor
  • Plasma exchange to filter antibodies out of the blood
  • Medicine to get rid of the antibodies, such as rituximab and cyclophosphamide

Other medicines may be used to manage things like seizures and problem behaviors.

Physical, occupational, and speech therapy may be used to help with recovery.


There are no known guidelines to lower the risk of this disease.


The Anti-NMDA Receptor Encephalitis Foundation 

Encephalitis Society 


Health Canada 

SickKids—The Hospital for Sick Children 


Anti-NMDAR encephalitis. Perelman School of Medicine—University of Pennsylvania website. Available at: Accessed May 20, 2020.

Anti-NMDA-receptor encephalitis. EBSCO DynaMed website. Available at:  . Updated September 1, 2016. Accessed May 20, 2020.

Anti-NMDA receptor encephalitis. SickKids—The Hospital for Sick Children website. Available at: Accessed May 20, 2020.

Graus F, Titulaer MJ, et al. A clinical approach to diagnosis of autoimmune encephalitis. Lancet Neurol. 2016 Apr;15(4):391-404, commentary can be found in Lancet Neurol 2016 Apr;15(4):349.

NMDAR antibody encephalitis. Encephalitis Society website. Available at: Updated September 2020. Accessed May 20, 2020.

What is Anti-NMDA receptor encephalitis? The Anti-NMDA Receptor Encephalitis Foundation website. Available at: Accessed May 20, 2020.

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