GAD - what is it

Can someone tell me what is the GAD test? What should your GAD be before going on the pump?

THe GAD is glutamic acid decarboxylase antibodies test. It’s basically a diagnostic tool to determine what kind of diabetes you have and if there’s any predisposition for your family members to have diabetes, specifically, type 1. It is also used to monitor the progression of type 1, which is why most doctors order it prior to pumping. As far as what the levels should be, that’s going to vary lab to lab. If I remember correctly, it’s more of a lower response that type 1’s have on the GAD.

Hope this helps!


Since you’re T2, your doctor probably wants a diagnosis. There’s no specific GAD result you need for a pump. If you need insulin for control, it will help.

GAD is a test that indicates that you are suffering from an autoimmune attack. About 80-90% of T1s and LADA patients will typically test positive for GAD. GAD is used by the medical profession to establish that you are suffering from autoimmune diabetes (so called type 1a, either classic juvenile T1 or LADA). Most doctors are more worried about your residual insulin production and will measure your fasting c-peptide. Some insurance companies still insist that you have a c-peptide below a certain level before agreeing to cover your pump.

In my view, a pump can be useful to any diligent insulin deficient diabetic, autoimmune or not. And asking that a diabetic “qualify” for insurance coverage based on their insulin production being compared to insulin production in other “normal” populations is stupid, particularly for an severely insulin resistant diabetic.

Just my thoughts for the day.

I was concerned with this issue, Since my c-peptide was 2.6 in Oct.(ususally considered normal) I wonderd if I really even need insulin. I don’t see anything on my lab results that look like a GAD, Does it have another name?

GAD is generally a separate test order, but it may also be lumped into a test named diabetes antibody profile or similar. It can be called GAD, Anti-GAD, GAD65, GAD ab, or something similar. But again, as I mentioned, the GAD is generally to establish whether you are T1.