Diabetes is a disease that causes increased levels of sugar or glucose to remain in the blood. A fasting blood glucose test is a reliable method to diagnose and maintain this common condition, as well as related disorders. This test is also called a fasting plasma glucose, or FPG, test and measures your blood glucose levels in a small sample of your blood after you have refrained from eating or drinking for several hours. This test is preferred by doctors because it is fast, inexpensive and it gives an accurate diagnosis of diabetes, along with other tests, even in individuals with no noticeable symptoms. See your doctor for a fasting blood glucose test to diagnose or check your diabetes.
Step 1
See your doctor to schedule a fasting blood glucose test. Your doctor will schedule an appointment to have blood drawn at the clinic or give you a requisition form to take to a blood lab. Read the instructions carefully and ask your doctor to explain anything you do not understand.
Step 2
Check your blood test time the evening before your fasting blood glucose test. Do not eat or drink anything except water for eight hours before the test. This means that if your blood test is scheduled at 7 a.m., you should not eat or drink anything after 11 p.m. the night before. To avoid excess hunger or low blood glucose levels, eat your regular evening meal an hour or two before you begin fasting.
Step 3
Do not eat breakfast or drink coffee or anything else the morning before your blood test. Fasting blood glucose tests are usually scheduled first thing in the morning because this makes it easier to fast for eight hours. Additionally, blood glucose levels are not affected by physical activity as much as they would be later in the day, which provides for more accurate measurements.
Step 4
Take a snack with you to your blood test appointment. You will be able to eat after blood is drawn. The blood test will be conducted by a nurse or medical assistant. Follow-up with your doctor to discuss your fasting blood glucose test results.
Tips and Warnings
- Fasting blood glucose test results can indicate a diabetes diagnosis, or uncontrolled blood glucose levels. A measurement of up to 100 mg/dL is considered normal. Blood glucose levels between 100 and 125 mg/dL indicate impaired fasting glucose, or a condition called prediabetes. A blood glucose levels= above 126 mg/dL indicate a diagnosis of diabetes.
- A fasting blood glucose test involves drawing blood with a needle, which can cause slight to moderate pain or stinging. The blood is usually drawn from a vein in the inner elbow, and the area is cleansed before the needle is inserted. Keep the area clean and covered with a small bandage after the blood test to limit the low risk of an infection.
