Which tube should a medical assistant use to draw a blood glucose level?

The gray top tube is specifically designed for testing blood glucose levels. It contains sodium fluoride, which acts as a glucose inhibitor, preserving the glucose levels in the blood sample for accurate testing. The presence of this additive helps prevent glycolysis, a process that could lower glucose levels if the sample is not tested promptly.

When drawing blood for glucose testing, a tube with this specific additive is essential to ensure reliable results. Other tube types do not contain the same preservatives, making them unsuitable for accurate glucose measurements. For example, the red top tube typically lacks additives, while the green top tube contains heparin, and the blue top tube is used for coagulation studies. Using the gray top tube ensures that the glucose sample remains stable until it is analyzed.