Glucose CPT: 82947


Blood Sugar

Expected Turnaround Time

Within 1 day

Specimen Requirements




1 mL

Minimum Volume

0.5 mL


Red-top tube or gel-barrier tube.


Separate serum from cells within 45 minutes of collection. Label specimen as serum.

Storage Instructions

Maintain specimen at room temperature.

Stability Requirements

Patient Preparation

Patient should fast for 12 hours.

Patient Information

To determine if your blood glucose level is within a healthy range; to screen for and diagnose diabetes and prediabetes and to monitor for high blood glucose (hyperglycemia) or low blood glucose (hypoglycemia); to check for glucose in your urine.

Blood glucose: when you are older than 45 years or have risk factors for diabetes; when you have symptoms suggesting high or low blood glucose; during pregnancy; when you are diabetic, self-checks up to several times a day to monitor blood glucose levels

Urine glucose: usually as part of a urinalysis.

A blood sample drawn from a vein in your arm or a drop of blood from a skin prick; sometimes a random urine sample is used. Some diabetics may use a continuous glucose monitor, which uses a small sensor wire inserted beneath the skin of the abdomen to measure blood glucose at frequent intervals and provides a result.

In general, it is recommended that you fast (nothing to eat or drink except water) for at least 8 hours before having a blood glucose test. For people with diabetes, glucose levels are often checked both while fasting and after meals to provide the best control of diabetes. For random, timed, and post-meal glucose tests, follow your health practitioner’s instructions.