Blood Sugar (Postprandial)

Overview

Postprandial blood sugar (PPBS) measures the concentration of glucose in the blood after eating, typically measured two hours after a meal. It evaluates how effectively the body produces and uses insulin to clear glucose from the circulation. This test helps detect impaired glucose tolerance, prediabetes, diabetes, gestational diabetes and reactive hypoglycaemia. Symptoms prompting a test include excessive thirst, frequent urination, unexplained weight loss, fatigue, blurred vision or episodes of sweating/lightheadedness after meals. Values can vary with age (older adults tend to have higher post-meal levels), pregnancy, stress, acute illness, medications (steroids, beta‑blockers), and body composition.

Test Preparation

• Overnight fasting (8-12 hrs) is required
• Do not eat or drink anything except water before the test
• Do not stop taking your thyroid medications on the day of the test unless otherwise advised by the doctor
• The urine sample must preferably be the first-morning midstream urine (part of urine that comes after the first and before the last stream)
• Collect the urine sample in a sealed and sterile screw-capped container provided by our sample collection professional
• Ensure that the urethral area (from where the urine is passed) is clean & the container doesn't come in contact with your skin
• Women are advised not to give the sample during the menstrual period unless prescribed
• For glucose PP: Sample to be given exactly 2 hours after starting meal or as advised by the physician
• Please note that it is mandatory to abide by the pre-scheduled sample collection time, as this will help us ensure the accuracy of the test results
• For the USG Whole Abdomen test: A
• Overnight fasting (8-12 hours) is required
• Do not eat or drink anything except water before the test
• B
• Drink plenty of water before the USG procedure to ensure a full bladder
• For TMT (Treadmill test): A
• Inform your doctor and technician if you may be pregnant before the test
• B
• Inform the technician about any pre-existing medical conditions such as heart disease, asthma, diabetes, and all medications you take before the test
• C
• Avoid heavy meals for at least 2 to 4 hours and caffeine (coffee, tea, energy drinks) and nicotine (cigarettes) for several hours before the test
• D
• Drink water to stay hydrated, but don't overhydrate right before the test
• For Echocardiography (Echo): A
• Remove any metal objects that may interfere with the electrodes
• If you have a pacemaker or other implanted cardiac devices, inform the technician
• B
• Wear comfortable clothing that allows easy access to your chest area, and avoid using oils, lotions, or creams on your chest area on the test day
• C
• Avoid consuming large amounts of caffeine (coffee, tea, energy drinks) before the test
• For X-ray: A
• Depending on the area to be imaged, you may be asked to wear a hospital gown at the time of the scan
• B
• You may have to remove your jewelry and any metal objects that might interfere with the image
• C
• Pregnant women should inform their doctor (and x-ray technician) as the radiation may affect the fetus
• If needed, precautions can be taken to lower the radiation exposure to the fetus
• For ECG: A
• Remove any metal objects that may interfere with the electrodes
• If you have a pacemaker or other implanted cardiac devices, inform the technician
• B
• Wear comfortable clothing that allows easy access to your chest area, and avoid using oils, lotions, or creams on your chest area on the test day
• C
• Avoid consuming large amounts of caffeine (coffee, tea, energy drinks) before the test
• For mammogram: Avoid using deodorants, antiperspirants, powders, lotions, creams or perfumes under your arms or on your breasts
• Metallic particles in powders and deodorants could be visible on your mammogram and cause confusion
• For PAP smear: Refrain from sexual activity for 2 to 5 days before the sample collection

Why Do I Need This Test

• Which profile is the test included in: Diabetes profile - Symptoms indicating need: polyuria, polydipsia, unexplained fatigue, recurrent infections, post-meal dizziness/sweating - Conditions diagnosed/monitored: prediabetes, type 2 diabetes, gestational diabetes, reactive hypoglycaemia - Reasons for abnormal levels: insulin resistance, inadequate insulin secretion, medication effects, acute stress/illness - Biological meaning: high values indicate impaired glucose handling; low values indicate excess insulin or inadequate intake - Lifestyle/family history: obesity, sedentary lifestyle, high-carb diet, family history of diabetes indicate testing

Understanding Test Results

• <70 mg/dL (<3.9 mmol/L): Suggests hypoglycaemia; may cause sweating, tremor, confusion; can result from excess insulin/medication, skipped meals, or reactive hypoglycaemia.
• 70–140 mg/dL (3.9–7.8 mmol/L): Considered normal two hours after a meal in non‑pregnant adults.
• 140–199 mg/dL (7.8–11.0 mmol/L): Indicates impaired glucose tolerance/prediabetes; higher cardiovascular and diabetes risk; warrants lifestyle intervention and further testing.
• ≥200 mg/dL (≥11.1 mmol/L): Consistent with diabetes if confirmed on a repeat test or accompanied by classic hyperglycaemic symptoms; may require diagnostic confirmation with fasting glucose, HbA1c or OGTT.
• For people with known diabetes, treatment targets may differ (commonly <180 mg/dL at 2 hours post-meal).

FAQs