Oral glucose tolerance test (OGTT): Dx. impaired glucose tolerance and diabetes mellitus. Do a fasting blood draw and then the patient ingests a 75 gm glucose load. Blood specimens obtained 1/2 hr, 1, 1 1/2 and 2 hours. Dx. diabetes mellitus when the plasma glucose level is >200mg/100ml.
Urinary glucose and acetone: tests glucose and acetone in the urine. Not all diabetics have these in their urine. Not specific for diabetes.