Plasma Glucose (1 hour after 50 g Glucose)

Specimen Required

Sodium Fluoride Vial (Sugar Vial)

Fasting Required

Purpose of the Test

The OGTT is used to diagnose diabetes, impaired glucose tolerance, and gestational diabetes. It may also be used to evaluate people with hypoglycemia (low blood sugar) or suspected insulin resistance.

When this test is required

This test is requested when there are symptoms of diabetes or when there are risk factors for diabetes, such as obesity, family history of diabetes, or high blood pressure. It may also be ordered for pregnant women to screen for gestational diabetes.

What the Test Detects

This test measures the amount of glucose in your blood 1 hour after ingesting a 50-gram glucose drink.

Preparation for the Test

To prepare for the test, you need to fast for at least 8 hours before the test. You should also avoid smoking and strenuous exercise prior to the test. Your doctor may ask you to stop taking certain medications that could affect the test results.

Sample Requirements

A blood sample is required for this test.

Additional Notes

The OGTT can cause nausea or vomiting in some people, and it is important to stay still during the test to avoid falsely elevating the blood glucose levels. Additionally, the OGTT is not always accurate and may need to be repeated or followed up with other tests for confirmation.

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