What’s involved in a glucose tolerance test?

September 01, 2020 | by Edward-Elmhurst Health
Categories: Healthy Driven Life

When your body’s blood sugar is too high, it could be a sign of prediabetes or diabetes.

Glucose intolerance is a general term for several conditions that cause the body to have higher-than-normal levels of blood sugar, including prediabetes, Type 1 and Type 2 diabetes, as well as gestational diabetes.

Some symptoms of glucose intolerance include:

  • Increased thirst
  • Frequent urination
  • Excess hunger
  • Fatigue
  • Blurred vision

To determine whether your blood glucose is too high, your doctor may order a glucose tolerance test.

A glucose screening test is a standard part of prenatal care during pregnancy. The screening test involves drinking a sweet liquid then having blood drawn an hour later to test blood glucose levels.

If that test is positive, pregnant women are asked to take a follow-up oral glucose tolerance test to check for gestational diabetes.

The glucose tolerance test is more extensive than the screening and involves fasting before the test.

  • First, you’ll eat or drink nothing but water for at least 8 hours before the test.
  • When you arrive at your appointment, you will have your blood drawn to measure your baseline glucose level.
  • Then you’ll drink the same sweet liquid, but more of it.
  • After that, technicians will draw your blood every two or three hours, measuring your body’s reaction to the glucose.

If you have high blood glucose at any two of the blood draws, you have gestational diabetes.

Doctors use the oral glucose tolerance test to diagnose prediabetes and Type 2 diabetes as well.

The Centers for Disease Control and Prevention reports 34.2 million Americans have diabetes, and 88 million people aged 18 years or older have prediabetes.

When left untreated, diabetes can potentially lead to heart disease, stroke, kidney or nerve damage. It’s important to work with your doctor to control your blood pressure, glucose and cholesterol levels, and maintain a healthy lifestyle.

Routine check-ups with your doctor can also help you assess your risk for diabetes and take steps to reduce it.

Schedule your lab test (including a glucose tolerance test) online or through the MyEEHealthTM mobile app.

We’re offering Video Visits for the care you need today, from the comfort of home. Learn more about Video Visits.

For updates on our planning and response efforts as we work to stop the spread of COVID-19, please check EEHealth.org/coronavirus.

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