Blood Urea Nitrogen
Alternative names: BUN, Urea Nitrogen, Urea, B.U.N.
Clinical Summary
MedlinePlus describes a blood urea nitrogen (BUN) test as a measure of the amount of nitrogen in your blood that comes from the waste product urea.
Higher-Than-Range Notes
MedlinePlus notes a high BUN level often suggests kidney damage or dysfunction, dehydration, or high protein intake.
Lower-Than-Range Notes
MedlinePlus notes low BUN levels are uncommon and can be associated with liver disease or malnutrition.
Commonly Measured Alongside
Longitudinal Tracking
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General Reference Information: This definition is sourced from public health reference libraries for patient education. It is not intended to substitute professional medical diagnosis, clinical reviews, or treatment plans. Always consult with a qualified health provider regarding your laboratory results.