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Random Blood Glucose Test

This procedure can provide a "snapshot" picture of the glucose concentration in your bloodstream

Overview

The way to test for diabetes is to measure your blood glucose level. A random test is done at any time, to get a "snapshot" picture of the glucose concentration in your bloodstream. In general, this can be determined from the few drops of blood obtained from a simple fingerstick, but your doctor may take blood from a vein in your arm.

A healthy blood glucose level is between 70 and 110 milligrams per deciliter (mg/dL). According to the guidelines of the American Diabetes Association, diabetes is diagnosed if the level is above 200 mg/dL in a random test, and the person has symptoms of diabetes.

What it's used for

This test is used to measure your level of blood glucose to diagnose diabetes.

Preparation

No preparation is necessary for this test.

How it's done

This test is done by collecting a small amount of blood, either from a fingerstick or from a vein. Blood glucose is then measured, and you will be informed of the results.

Follow-up

If you or your child is diagnosed with diabetes, a diabetes education program will be started with your doctor or a specialist (for example, a certified diabetes educator) to whom you are referred. Most children are hospitalized when diagnosed with type 1 diabetes for medical stabilization, to determine appropriate insulin doses and, equally important, to begin the educational process about treating and living with diabetes in this structured and helpful setting.

If someone has symptoms of diabetes but the random blood glucose level is below 200 mg/dL, the doctor will want to follow up with a fasting blood glucose test or other test.

Risks

There are no risks to this test.

When to call your doctor

Call your doctor if you or your child has continuing symptoms of diabetes.

Additional information

For some people, especially those with symptoms of diabetes, a random blood glucose test is all that is needed to diagnose diabetes.