Glucose Tolerance Test

Excerpt

A glucose tolerance test (GTT) is a procedure that determines whether a patient can use and store glucose normally. The test is usually used to test for diabetes mellitus, insulin resistance, impaired pancreatic beta cell function, and sometimes reactive hypoglycemia or acromegaly, or rarer disorders of carbohydrate metabolism. In the most commonly performed version of the test, an oral glucose tolerance test (OGTT), a standard dose of glucose is ingested by mouth, and blood levels are checked two hours later. Many variations of the GTT have been devised over the years for various purposes, with different standard doses of glucose, different administration routes, different sampling intervals, and various substances measured in addition to blood glucose.