Glucose, Plasma (Fasting) by Mass Concentration

Why Is This Test Done?

Your healthcare provider may order this test to diagnose or monitor conditions like type 1 or type 2 diabetes, prediabetes, or to evaluate how your body processes glucose. It’s often part of a broader metabolic screening, especially if you have risk factors like obesity, a family history of diabetes, or symptoms like excessive thirst or fatigue.

What to Expect Before the Test

You’ll need to fast (not eat or drink anything except water) for at least 8 hours before the test. Avoid caffeine or smoking. Bring any medications you’re currently taking, as some may affect results.

How the Test Is Performed

A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but it’s usually over quickly. The blood sample is then sent to a lab for analysis.

What the Results Mean

Results are typically reported as a numerical value representing glucose concentration in your plasma. While reference ranges vary by lab, higher than expected levels may signal diabetes or insulin resistance, while lower levels could indicate hypoglycemia or other metabolic issues. Your doctor will interpret results in the context of your overall health.