Normal range 7-20 mg/dL (2.5-7.1 mmol/L (urea) SI). Specimen: Serum or plasma.
Also known as: urea nitrogen, urea.
7-20 mg/dLThreshold: read below
Reference range
Conventionalmg/dL
720
SImmol/L (urea)
2.57.1
Combined adult band. LabVals does not publish separate men's, women's, or pediatric ranges for Blood Urea Nitrogen (BUN); those can be narrower than the band shown.
Blood Urea Nitrogen (BUN) reference range, specimen, and conversion details
Convert any Blood Urea Nitrogen (BUN) result between units on the unit converter.
What is the normal range for Blood Urea Nitrogen (BUN)?
The standard teaching reference range for Blood Urea Nitrogen (BUN) is 7-20 mg/dL in conventional units, or 2.5-7.1 mmol/L (urea) in SI units. This value is measured in serum or plasma.
What threshold is taught for Blood Urea Nitrogen (BUN)?
For Blood Urea Nitrogen (BUN), the commonly taught threshold is: > 100 mg/dL suggests serious renal impairment.
Source: Adult reference values compiled from Pagana & Pagana, Mosby's Diagnostic and Laboratory Test Reference, and Fischbach & Dunning, A Manual of Laboratory and Diagnostic Tests. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.
Rises with dehydration even when kidneys are healthy - read with creatinine.
Elevated BUN contributes to the nausea and confusion of uremia.
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