Making the Diagnosis
To diagnose diabetes, doctors will take a medical history (asking about symptoms and other medical conditions), perform a physical examination, and check for high blood sugar levels. If your blood sugar levels are high, your doctor will likely check your blood sugar levels again to confirm the diagnosis.
When your blood is tested, you may be asked to fast (not eat or drink fluids other than water) for at least 8 hours, or you may be asked to drink a glucose solution and wait for 2 hours to test your blood. You may also have to follow some specific instructions before your blood is tested.