NMDA receptor antibody test
Quick answer: This test looks for antibodies against the NMDA receptor (NR1 subunit), a protein on brain cells. Doctors usually order it when they suspect autoimmune encephalitis, for example with sudden behaviour changes, seizures or memory problems.
- SampleBlood
- TakesAbout 5 minutes for blood; longer if spinal fluid is also collected
- Before the testNo special preparation is usually needed.
- In fertility careIn young women this condition can be linked to an ovarian teratoma, so doctors may also arrange a pelvic scan.
How the test is done
- 1A nurse draws a tube of blood from your arm
- 2Your doctor may also request spinal fluid from a lumbar puncture
- 3The sample is sent for a cell-based antibody test
- 4The lab reports whether NMDA receptor antibodies are present
What your results can mean
Reading your report
A positive result does not by itself confirm a disease, because some healthy people test positive; your doctor reads it with your symptoms and other tests.
If the result is outside the usual range
A positive result, especially in spinal fluid, can point to anti-NMDA receptor encephalitis. Blood alone can sometimes be negative or weakly positive, so doctors often test spinal fluid too.
Who usually has this test
People, often young women, with sudden changes in behaviour, confusion, seizures, abnormal movements or memory problems.
Risks and aftercare
The blood draw needs no aftercare; follow staff advice if a lumbar puncture is also done.
Names and options
Also called: anti-NMDAR, NR1 antibody, NMDA encephalitis test
Listed by the hospital as
- NMDA RECEPTOR ANTIBODY (NR1)
Questions about this test
Why might a pelvic scan be ordered with this test?
In women, anti-NMDA receptor encephalitis can be linked to an ovarian teratoma, a type of usually non-cancerous cyst. Finding and removing it can help recovery.
Is spinal fluid testing more reliable for NMDA antibodies?
Spinal fluid is generally more sensitive and specific for this antibody than blood. Many doctors test both.
Can people recover from anti-NMDA receptor encephalitis?
Many people improve substantially with treatment, though recovery can take months. Early diagnosis helps.
Related tests
Tamara Hospital & IVF Centre, Rajajinagar
34/3, 10th Cross Road, opp. Vardhaka Sardar Patel School, 1st N Block, 2nd Stage, Rajajinagar, Bengaluru 560010
The hospital is open 24 hours. Call before you come to check the timing for your scan or sample collection.
Get directions ↗IVF Pulse fertility care at Tamara Hospital →
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This page explains each test in general terms so you know what to expect. It is not medical advice: your doctor decides which tests you need and what your results mean. Reference ranges differ between laboratories. Updated 4 November 2026.