BUN/Creatinine Ratio

OtherKidneyBlood

The BUN/creatinine ratio compares blood urea nitrogen — a waste product from protein breakdown — with creatinine — a waste product from muscle metabolism. Both are filtered by the kidneys, and their ratio gives kidney-function context.

Why it matters: A higher ratio can reflect dehydration, recent high-protein intake, or upper gastrointestinal bleeding. A typical or lower ratio with elevated creatinine often points more toward kidney filtering changes than dehydration.

What Moves It

May increase with:

Dehydration
Gastrointestinal bleeding
High protein diet

May decrease with:

Liver disease
Low protein intake
Associated Conditions
Chronic kidney diseaseAcute kidney injury
Related Markers
BUNCreatinine
Common questions

What is BUN/Creatinine Ratio?

The BUN/creatinine ratio compares blood urea nitrogen — a waste product from protein breakdown — with creatinine — a waste product from muscle metabolism. Both are filtered by the kidneys, and their ratio gives kidney-function context.

What might a high or low BUN/Creatinine Ratio mean?

A higher ratio can reflect dehydration, recent high-protein intake, or upper gastrointestinal bleeding. A typical or lower ratio with elevated creatinine often points more toward kidney filtering changes than dehydration.

What can affect BUN/Creatinine Ratio?

It may be higher with: Dehydration, Gastrointestinal bleeding, High protein diet. It may be lower with: Liver disease, Low protein intake.

More in Other
eGFR (African American)eGFR (Non-African American)

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