Glucose Tolerance Test

INDICATIONS

  • Fasting glucose level -100-126 mg/dl
  • Family history of diabetes mellitus
  • Unexplained retinopathy, neuropathy
  • Nephropathy, hypercholesteremia, diseases of coronary vessels, peripheral vascular disease, cerebrovascular diseases, especially in adults under 50 years old.
  • Glycosuria even if blood glucose level is normal.
  • Spontaneous abortions, premature birth, abundance of water at pregnancy, still birth, big fetus, history of gestational toxicosis.
  • Gestational diabetes
  • Reactive hypoglycemia

METHOD

  • Glucose 75 g + water 300 ml shall be orally administered during 5 minutes with subsequent measurement of blood sugar: at once, 1 hour later and 3 hours later.

Results

  • Within 0-2 hours – >200 mg/dl – diabetes
  • Glucose level within 140-199 mg/dl – glucose intolerance (attention should be paid as diabetes is diagnosed in 40 % of cases).
  • Glucose level within 140-199 mg/dl and fasting glucose level within 100-126 mg/dl – impaired glucose tolerance
  • 3 hours – glucose level < 60 mg/dl – reactive hypoglycemia.