fbs (fasting blood sugar)
DiabetesBlood sampleResults Same dayFasting required
FBS (Fasting Blood Sugar)
Measures your blood glucose after an overnight fast. A core screening test for diabetes and prediabetes.
Sample
Blood
Results
Same day
Fasting
Required
Follow-up
Optional add-on
What this test detects
Fasting glucose
Hexokinase · plasma
Quantitative · mg/dL
When to get this test
Diabetes screening
Helps screen for diabetes and prediabetes, especially if you have risk factors like family history or being overweight.
Monitoring blood sugar
Tracks how well your blood sugar is controlled if you already have diabetes or borderline results.
Symptom check-up
Useful when you have symptoms like excessive thirst, frequent urination, or unexplained fatigue.
How to prepare
01
Fast for 8–12 hours before the blood draw; water is allowed.
Common questions
Can I drink water while fasting?
Yes. Plain water is allowed and even encouraged so you stay hydrated for the blood draw.
What counts as a normal fasting result?
Generally, a fasting glucose below 100 mg/dL is considered normal, but your result should always be interpreted alongside your overall health.
Can I take my medicines before the test?
Most maintenance medicines may be continued, but please follow the advice of the doctor who ordered the test regarding diabetes medication timing.