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Blood urea nitrogen
Blood test / From Wikipedia, the free encyclopedia
"BUN" redirects here. For other uses, see Bun (disambiguation).
Blood urea nitrogen (BUN) is a medical test that measures the amount of urea nitrogen found in blood. The liver produces urea in the urea cycle as a waste product of the digestion of protein. Normal human adult blood should contain 7 to 18 mg/dL (0.388 to 1 mmol/L) of urea nitrogen.[1] Individual laboratories may have different reference ranges, as they may use different assays.[2][3][4] The test is used to detect kidney problems. It is not considered as reliable as creatinine or BUN-to-creatinine ratio blood studies.[1]