BUN / Cr
A ratio that helps distinguish causes of elevated BUN.
What is it
The BUN-to-creatinine ratio helps distinguish kidney-based versus hydration-based causes of BUN elevation.
Why it's measured
The BUN/creatinine ratio has been used in research and clinical practice to interpret kidney panel findings.
Reference range
Standard laboratory reference
10 – 20 ratio
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
What results may indicate
Elevated
Higher ratios have been associated with dehydration or GI bleeding in research literature.
Lower
Lower ratios may reflect low protein intake or certain liver conditions.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
Calculated from BUN and creatinine.
Related markers
Common questions
The BUN-to-creatinine ratio helps distinguish kidney-based versus hydration-based causes of BUN elevation.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. BUN : Creatinine Ratio is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
BUN : Creatinine Ratio is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Find the right panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.
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