Glucose (Serum) – Quantitative Measurement

Why This Test Is Done

Doctors order glucose tests to check for conditions such as diabetes, where blood sugar levels are too high or too low. It may also be used during pregnancy to screen for gestational diabetes or before surgery to evaluate your body’s ability to handle stress. Some tests are done to monitor long-term health in people with known diabetes or other metabolic conditions.

How the Test Is Performed

A healthcare provider will insert a small needle into a vein in your arm to collect blood. You may feel a slight sting, but it usually takes only a few seconds. The blood is then sent to a lab for analysis using an enzymatic method, which measures how quickly glucose reacts with an enzyme to produce a detectable signal.

What the Results Mean

Results are typically reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). While exact reference ranges can vary by lab, values outside of normal ranges may indicate potential health issues that need further evaluation by your doctor.

Possible Causes of Abnormal Results

High glucose levels may be caused by diabetes, poor diet, stress, illness, or certain medications. Low glucose levels (hypoglycemia) can result from excessive insulin, certain medications, or prolonged fasting. Your doctor will discuss these findings with you and may recommend further testing or adjustments to your treatment plan.