The fasting blood glucose test (FBS) measures the amount of glucose (sugar) in your child’s blood before your child has had anything to eat or drink for at least 8 hours. It is also called a fasting plasma glucose test.
The most common use of this test is to check for diabetes. The body breaks down some of the foods your child eats into glucose. The blood carries the glucose to the cells of your child’s body. Your child needs some glucose in his cells for energy, but too much glucose in the blood is not good for your child’s health. Blood glucose that stays high is the main problem of diabetes.
Your healthcare provider will tell you when your child should stop eating and drinking before the test. In most cases your child should eat nothing and drink nothing but water for at least 8 hours before the test. Make sure your child drinks plenty of water before the test.
Your child may need to avoid taking certain medicines before the test because they might affect the test result. Make sure your healthcare provider knows about any medicines, herbs, or supplements that your child is taking. Ask your provider before stopping any of your child’s regular medicines.
Talk to your child's healthcare provider if you have any questions about the test.
Your healthcare provider may poke your child’s finger with a small needle (lancet) and fill a small tube with the blood, or take a small amount of blood from the arm with a needle. The blood is sent to a lab.
Having this test will take just a few minutes.
Ask your healthcare provider when and how you will get the result of the test.
Blood glucose level may be higher than normal (hyperglycemia) if:
Test results are only one part of a larger picture that takes into account your child's medical history and current health. Sometimes a test needs to be repeated to check the first result. Talk to your healthcare provider about the result and ask questions, such as: