What is the Blood Urea Nitrogen (BUN) Test?

The Blood Urea Nitrogen (BUN) Test measures the amount of nitrogen in the blood that comes from urea, a waste product formed when the body breaks down protein. Urea is filtered by the kidneys, so this test is commonly used to evaluate kidney function and overall metabolic health.

Who should take this test?

• Patients with suspected kidney disease.
• Individuals with dehydration or fluid imbalance.
• People with abnormal kidney function tests (KFT).
• Patients with symptoms like fatigue, swelling, or reduced urine output.
• Doctor-advised monitoring of renal or metabolic conditions.

Preparation & Test Process

How to interpret results

The test reports the level of blood urea nitrogen (BUN).

High levels may indicate kidney dysfunction, dehydration, or high protein breakdown.
Low levels may be seen in liver disease or poor nutrition.

Results are usually interpreted along with creatinine and other kidney function tests.

FAQs – Blood Urea Nitrogen (BUN) Test