What is this test?
- This laboratory test is performed on a blood sample to measure the levels of glucose after two hours of having a meal containing 75grams of glucose. Normally, glucose levels return to normal within 2 hours after having a meal. If the glucose levels are still high, it may help in diagnosing diabetes.
Why is this test performed?
- To help in the diagnosis of type-I and type-II diabetes mellitus
- To screen for gestational diabetes
- To detect the complications from diabetes
- To monitor the efficacy of anti-diabetic treatment.
WHAT DOES THE TEST MEASURES?
In diabetes blood, sugar levels are consistently high, over time high glucose levels can damage the body and can lead to many other problems. This test measures blood sugar levels after lunch/dinner.
- How to prepare for this test?
An adequate meal containing 75grams of glucose should be taken 2 hours prior to the test. Inform your doctor about the use of all prescribed and non-prescribed medicines before the test. Wear a short-sleeved shirt to aid the collection of sample.
- What will affect my test results?
- Stress
- Smoking
- Exercise after the meal
- Candy/snack consumption after meal
- Incomplete meal.
- What are the risk factors for diabetes?
Following condition may increase your risk to develop diabetes:
- Obesity
- Sedentary lifestyle
- Family history of diabetes
- Hypertension
- More than 45 years of age
- What are the risks of this test?
Collecting blood from a vein is a very easy procedure and pose only minimum risk, including:
- Bruising
- Bleeding
- Infection
- What are the symptoms of high blood sugar?
- Increased thirst
- Frequent urination
- Blurring of vision
- Fatigue
- Weakness
- What are other causes of high blood glucose?
- Hyperthyroidism
- Acromegaly
- Chronic kidney disease
- Steroid therapy
- Stress
- Cushing syndrome
- Pancreatitis
- What are the causes of low blood glucose?
Following conditions may cause low blood glucose levels:
- Liver disease
- Alcohol abuse
- Adrenal insufficiency
- Hypothyroidism
- Starvation
- Insulin overuse
- Kidney disease
- Severe infections
Normal range for 2 hour postprandial glucose:
Adults (Below 50 years): Less than 140 mg/dL
Older adults (Above 50 years): Less than 150mg/dL
- Interpretation of test results:
- If glucose levels two hours after the administration of food are between 140-200mg/dL, it may indicate pre-diabetes
- If glucose levels two hours after the administration of food are greater than 200mg/dL, it may indicate diabetes mellitus because the pancreas may not be producing proper amounts of insulin.
