Blood Glucose

2-hour Postprandial Blood Sugar Test, Fasting Blood Sugar Test, Random Blood Sugar Test

How To Prepare

Fasting blood sugar (FBS)

For a fasting blood sugar test, do not eat or drink anything other than water for at least 8 hours before the blood sample is taken.

If you have diabetes, you may be asked to wait until you have had your blood tested before taking your morning dose of insulin or diabetes medication.

2-hour postprandial blood sugar

For a 2-hour postprandial test, eat a meal exactly 2 hours before the blood sample is taken. A home blood sugar test is the most common way to check 2-hour postprandial blood sugar levels.

Random blood sugar (RBS)

No special preparation is required before having a random blood sugar test.

Talk to your health professional about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results may indicate. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

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Author:	Caroline Rea, RN, BS, MS	Last Updated: July 25, 2007
Medical Review:	Caroline S. Rhoads, MD - Internal Medicine Alan C. Dalkin, MD - Endocrinology
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