Skip to content

Anti-GAD65 Antibody (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the presence of antibodies directed against the GAD65 protein, which is linked to certain autoimmune conditions affecting the nervous system.

Quick summary

["This test helps diagnose or monitor conditions like type 1 diabetes or autoimmune neurological disorders."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
72523-4
Short code
GAD65 Ab SerPl Ql IF
Synonyms
GAD65 Ab SerPl Ql IF
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
if
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What Is This Test Measuring?

Anti-GAD65 antibodies are proteins produced by the immune system that mistakenly target the GAD65 protein, which plays a role in insulin production and nerve function. This test detects these antibodies in your blood to identify potential autoimmune activity.

Why Might This Test Be Ordered?

Your healthcare provider may order this test if you have symptoms like unexplained diabetes, nerve pain, or other neurological issues that could be linked to autoimmune disorders affecting the pancreas or nerves.

How Is the Sample Collected?

A blood sample is drawn from a vein in your arm by a healthcare professional. The blood is then processed into serum or plasma for testing.

What Are Common Results?

Results are qualitative (positive or negative) and indicate whether antibodies are present. Elevated levels may suggest an autoimmune condition, but further testing and clinical correlation are needed.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: This test is important for diagnosing or supporting a diagnosis of autoimmune disorders such as type 1 diabetes, stiff-person syndrome, or other neurological conditions where GAD65 antibodies are involved. It helps guide treatment decisions and monitor disease progression.

Short name

Anti-GAD65 Antibody

Frequently asked questions

What does a positive result mean?
A positive result means your immune system has detected and produced antibodies against the GAD65 protein. This can be a sign of an autoimmune condition, but it does not diagnose the specific disorder alone. Your doctor will consider your symptoms, medical history, and other test results to make a full assessment.
How long does it take to get results?
Results are typically available within 24 to 72 hours, depending on your lab’s processing schedule. Your healthcare provider will contact you with the results once they are ready.
Can lifestyle changes affect this test?
While certain medications or autoimmune conditions may influence antibody levels, lifestyle factors like diet or stress generally do not directly affect this specific antibody test. Always follow your doctor’s advice regarding any treatments or lifestyle adjustments.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy