A glucose test, is done with the purpose of checking the amount of sugar in your blood, which is called glycemia. This is why it is the main test requested to diagnose diabetes.
This test is a fasting test, so it should be performed after 8 hours of not eating or drinking anything. So that the result is not influenced and the probability of getting a false positive result for diabetes is decreased for example. As soon as the results come out, the doctor may indicate readjustments to your diet, the use of antidiabetic medication, such as Metformin, for example, or even insulin.
The reference range for fasting glucose tests are:
- Normal: less than 99 mg / dl;
- Pre-diabetes: between 100 and 125 mg / dl;
- Diabetes: greater than 126 mg / dl on two different days.
The fasting time for the fasting glucose test is 8 hours, and so you should not eat or drink anything during this time. In addition, you should not smoke before the test and should avoid making any type of exertion.
Do the test below, to find out if you are at risk of having diabetes:
Glucose tolerance test
The glucose tolerance test, also called a glucose curve test or OGTT, is done also a fasting test and consists of glucose or dextrosol intake after the first collection. In this testing there are various dosages of glucose taken: after fasting, 1, 2 and 3 hours after ingestion of the sugary liquid provided by the laboratory, being necessary that you remain in the laboratory practically all day.
This test can help the doctor diagnose diabetes and is usually done during gestation, since it is common for glucose levels to increase during this time. See how a glucose tolerance test is done.
OGTT reference range
The reference range of a glucose tolerance test refers to the glucose value 2 hours or 120 minutes after glucose intake and they are:
- Normal: less than 140 mg / dl;
- Pre-diabetes: between 140 and 199 mg / dl;
- Diabetes: equal to or greater than 200 mg / dl.
Therefore, if you have a fasting plasma glucose greater than 126 mg / dl and a blood glucose level of 200 mg / dl or greater than 2 h after ingesting glucose or dextrosol, you are likely to have diabetes, and the doctor should indicate the treatment.
Glucose testing during pregnancy
During pregnancy it is possible for women to have changes in their blood glucose levels, so it is important that your obstetrician requests the dosage of glucose to check if you may have gestational diabetes.
The requested test may be either fasting glucose or the glucose tolerance test, whose reference values are different.