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Biochemistry Diabetes Home collection available

Glucose Fasting (Plasma) (FBS)

Also known as: Glucose fasting

Parameters1 tested
SampleBlood
Fasting10-12 hrs
Report inSame day

How to prepare

Fasting needed

Do not eat for 10-12 hrs before the test. Plain water is fine.

Good to know

Fast for 10–12 hours before the test (only water allowed). Take your usual medicines unless your doctor says otherwise.

Medicines

Tell our phlebotomist about any medicines you take. Don't stop them without asking your doctor.

Comfortable clothes

Wear a loose sleeve so the sample can be taken easily from your arm.

How it works

Book onlinePick a time slot
Home visitSealed, sterile kit
Lab testingBarcode tracked
ReportIn same day

About this test

Fasting blood sugar measures the glucose in your blood after not eating for 8–12 hours. It is a basic test to screen for and monitor diabetes.

Why is this test done?

  • Screen for diabetes
  • Monitor diabetes treatment
  • Check sugar in pregnancy

Symptoms — when should you get tested?

  • Frequent urination and thirst
  • Tiredness
  • Weight loss
  • Blurred vision

Normal range

Normal 70 – 99 mg/dL
Prediabetes 100 – 125 mg/dL
Diabetes 126 or more mg/dL

Reference ranges differ slightly between labs, methods, age and sex. Always discuss your report with your doctor.

If your result is high

A high fasting sugar suggests diabetes or prediabetes (confirmed by a repeat test or HbA1c).

Common reasons
  • Diabetes
  • Stress or illness
  • Steroid medicines
  • Not fasting properly

If your result is low

Low sugar (below 70 mg/dL) can cause shakiness, sweating and confusion.

Common reasons
  • Too much diabetes medicine or insulin
  • Skipping meals
  • Alcohol
  • Rarely, insulin-producing tumours

How is the test done?

  1. 1
    Book online

    Choose your slot for home collection or a visit to our centre.

  2. 2
    Blood sample taken

    A trained phlebotomist takes a small blood sample from a vein in your arm with a sealed, single-use needle. It takes about 2 minutes.

  3. 3
    Tested in our lab

    Your barcoded sample is tested on automated machines with strict quality checks.

  4. 4
    Report on WhatsApp

    A pathologist checks the result and the report reaches you on WhatsApp and email.

Save more with a health package

This test is also included in these checkups along with many other tests.

Basic Health Checkup 6 tests · 15 parameters
Contact for price
Full Body Checkup – Essential 10 tests · 21 parameters
Contact for price
Full Body Checkup – Advanced 14 tests · 31 parameters
Contact for price

Frequently asked questions

Yes, plain water is allowed. Avoid tea, coffee and juice.

Yes. Please fast for 10-12 hrs before your sample is collected. You can drink plain water.

Your report is usually ready in same day after the sample reaches our lab. We send it on WhatsApp and email, and you can also download it from the Reports page.

Please call our team to confirm whether home sample collection is available for your location and test.

This test needs a blood sample. Fast for 10–12 hours before the test (only water allowed). Take your usual medicines unless your doctor says otherwise.

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