Glucose Tolerance Test

**Semantic type:** Laboratory Procedure

**Definition:** A test that involves administration of a know quantity of glucose as a means of screening for glucose intolerance or diabetes mellitus. Typically a baseline (fasting plasma or serum glucose) is drawn prior to the administration of the glucose bolus. Serial plasma glucose levels are obtained (e.g. 30min, 1hr, 2hr, 3hr) and a plot of plasma glucose versus time is created. Comparison of these values against standardized results can be used in establishing the diagnosis of glucose intolerance or diabetes mellitus.