Glucose, Serum (Mass Concentration)

Why Is This Test Done?

Your healthcare provider may order this test to monitor conditions like diabetes, check for signs of low blood sugar (hypoglycemia), evaluate how your body responds to medications, or assess metabolic health. It’s also used during pregnancy to track glucose levels or before certain surgeries.

What to Expect Before the Test

No special preparation is usually needed, but you may be asked to fast (not eat or drink) for 8–12 hours before the test if it’s part of a glucose tolerance test. If fasting isn’t required, you can eat and drink normally. Bring any medications you’re taking with you.

What Happens During the Test?

A healthcare provider will clean the area on your arm, insert a small needle to draw blood, and collect a few drops into a tube. The process takes just a few minutes, and you may feel a slight pinch. The blood sample is then sent to a lab for analysis.

What Are the Results Mean?

Results are reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). While reference ranges vary by lab, higher or lower-than-expected results may signal potential issues like diabetes, insulin resistance, or other metabolic disorders. Your provider will interpret the results in the context of your health.