Kidney

Blood Urea Nitrogen

A measure of urea nitrogen in the blood, often used in kidney testing.

kidneyproteinmetabolismelectrolytes

About this biomarker

Blood urea nitrogen, or BUN, reflects a waste product formed when the body breaks down protein. It is cleared by the kidneys and is often read with creatinine.

Why it matters

It adds context to kidney function, hydration, and protein metabolism.

What lower levels may suggest

Low BUN may be seen with low protein intake, liver disease, or overhydration.

What higher levels may suggest

High BUN may be seen with reduced kidney function, dehydration, high protein intake, or gastrointestinal bleeding.

Common tests

Basic metabolic panel, comprehensive metabolic panel, kidney function panel

Your trend

Loading your results…
Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about your health.