Fasting Blood Sugar Test
250 Kshs | Home Collection Available
Synonyms
glucose, plasma, blood sugar, random blood sugar
Purpose
The Fasting Blood Sugar (FBS) Test is a blood test that measures the amount of glucose in your blood after fasting for 8 to 12 hours. It helps assess how your body regulates blood sugar without the influence of recent meals.
This test is important for the early detection, diagnosis, and monitoring of diabetes mellitus and prediabetes. It also helps evaluate blood sugar control in individuals with a known history of diabetes.
To get a more comprehensive picture of glucose metabolism, the FBS test is often done alongside other tests such as HbA1c (Glycated Hemoglobin), Oral Glucose Tolerance Test (OGTT), Random Blood Sugar (RBS), and C-peptide and Insulin levels.
Patient Preparation
The patient should avoid caloric intake for at least eight hours before the test.
Samples
Entire collection with a minimum volume of 0.5ml of plasma collected in a grey top tube (sodium fluoride) or green top tube (lithium heparin). Plasma should be separated within 45 minutes of sample collection. Store the sample at room temperature.
Reference Range
65-99 mg/Dl, prediabetes 100-125mg/dl, diabete>125mg/dl
Results Turnaround
Within 24 hours of receipt of samples.
Diseases / Diagnostic indicators
The FBS test helps detect several blood sugar-related disorders:
High Fasting Blood Sugar (Hyperglycemia):
May indicate diabetes mellitus or prediabetes. Persistent high levels suggest the body is not effectively using insulin or producing enough of it.
Low Fasting Blood Sugar (Hypoglycemia):
Could signal conditions like insulinoma (insulin-producing tumor), neuroglycopenia (low glucose affecting brain function), or other endocrine disorders.
Normal Range:
Typically between 70–99 mg/dL. Results outside this range may prompt additional tests for acidosis, metabolic dysfunction, or pancreatic disorders.
Early detection through FBS testing enables timely diagnosis, lifestyle changes, or treatment to manage or prevent serious complications. For more on Fasting Blood Sugar Test, read this study.