Diabetes Symptoms and Tests

What should I do if I think I have diabetes?

The first step is to take our online risk test at diabetes.org/RiskTest and make an appointment with your doctor if you’re at higher risk for diabetes. Only your doctor can tell you for sure if you have diabetes or not.
Don’t delay—early detection and treatment of diabetes decreases the risk of developing the complications of diabetes.

What are the symptoms?

You may have no noticeable symptoms or only mild symptoms for years before diabetes is diagnosed.

Common signs and symptoms of type 2 diabetes include:

  • Urinating more than usual
  • Feeling very thirsty
  • Feeling hungry even after eating
  • Feeling tired
  • Having blurred vision
  • Having frequent infections or slow-healing cuts and sores
  • Weight loss—even though you are eating more (type 1)
  • Having tingling, pain, or numbness in the hands or feet (type 2)

How is diabetes diagnosed?

There are several ways to diagnose diabetes and each way usually needs to be repeated on a second day to be sure you have it. Testing should be carried out in a health care setting (such as
If your doctor determines that your blood glucose level (also called blood sugar) is very high, or if you have classic symptoms of high blood glucose in addition to one positive test, your doctor may not require a second test.


The A1C test tells you your average blood gluclose over the past 2 to 3 months. The advantage of the A1C test is that you don’t have to do anything to get ready for it. Diabetes is diagnosed at: A1C: 6.5% or higher.

Fasting Plasma Glucose (FPG)

This test checks your blood glucose after not eating or drinking anything (except water) for eight hours. Diabetes is diagnosed at:
Fasting blood glucose: 126 mg/dL or higher.

Oral Glucose Tolerance Test (also called the OGTT)

The OGTT is a two-hour test that checks your
blood glucose levels before and two hours after you drink a special sweet liquid. It tells the doctor how your body processes glucose. Diabetes is diagnosed at: Two-hour blood glucose: 200 mg/dL or higher. Random (also called Casual) Plasma

Glucose Test

If you are showing severe diabetes symptoms, your doctor may use a random glucose test. Diabetes is diagnosed at: Blood glucose: 200 mg/dL or higher.

What is prediabetes?

Prediabetes is a condition that occurs when your blood glucose is higher than normal but not high enough to be diabetes. This condition puts you at risk for developing type 2 diabetes.
Results indicating prediabetes are:
An A1C of 5.7%–6.4%
Fasting blood glucose of 100–125 mg/dL Two-hour blood glucose of 140 mg/dL–199 mg/dL