Serum/Plasma Glucose Concentration (Quantitative)

Why It’s Done

Your healthcare provider may order this test to diagnose or manage conditions like diabetes, prediabetes, hypoglycemia, or to check for metabolic disorders. It may also be done during pregnancy, before surgeries, or to evaluate symptoms such as excessive thirst, frequent urination, or unexplained weight changes.

What to Expect

A small blood sample is taken from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause discomfort. If you’re fasting (not eating or drinking), your provider will let you know how long to avoid food and liquids before the test.

Fasting vs. Non-Fasting Results

If your test is done while fasting, it provides a clearer picture of how your body processes glucose. Non-fasting results may include additional factors like recent meals or snacks, so your provider will note whether fasting was required.

Possible Causes of Abnormal Results

High glucose levels may indicate diabetes, poor insulin function, or conditions like pancreatitis or Cushing’s syndrome. Low levels could signal hypoglycemia, liver disease, or certain medications. Always discuss results with your provider.