The Glucose Tolerance Test (GTT) measures the body's ability to process glucose by taking blood samples before and after consuming a glucose solution, commonly used to diagnose diabetes or gestational diabetes.
Patient must be fasting. No food, drinks or energy supplying substances in any form should be consumed for at least 8 hours prior to the test, but the patient must not fast longer than 16 hours. Water is permitted throughout the fasting period and during the test.
Patient should avoid excessive exercise during the fasting period.
Smoking is not permitted during the fasting period or throughout the test.
The patient must rest during the test, preferably either sitting or lying in a semi-recumbent position (as lying flat can delay the gastric emptying).
Patients should remain at the collection centre for the duration of the test.
The GTT must be performed in the morning because of a decreasing glucose tolerance in the afternoon.
Should you have any queries regarding these instructions, please contact our nearest centre listed on the back of your request form.
