Glucose

A glucose test measures the amount of glucose (sugar) in your blood. It is used to diagnose and monitor conditions related to blood sugar levels, such as diabetes.

You might need a glucose test if you have symptoms of diabetes (e.g., frequent urination, excessive thirst), are at risk for diabetes, or need to monitor your blood sugar levels if you have already been diagnosed with diabetes or other metabolic disorders.

Common types include the fasting blood glucose test (measuring blood sugar after fasting for at least 8 hours), the oral glucose tolerance test (OGTT), which involves fasting overnight and then drinking a glucose solution, and the hemoglobin A1c test, which measures average blood sugar levels over the past 2-3 months.

For a fasting glucose test, you should avoid eating or drinking anything except water for 8-12 hours before the test. For an OGTT, you may need to follow specific instructions provided by your healthcare provider, including fasting and drinking a glucose solution.

A normal fasting blood glucose level is typically between 70 and 99 mg/dL (milligrams per deciliter). Levels between 100 and 125 mg/dL are considered prediabetic, while levels of 126 mg/dL or higher may indicate diabetes.