Blood Urea Nitrogen (Canine)

Also known as:BUNUrea

Reference Range

Critical Low

mg/dL

Reference Range

7-27

mg/dL

Critical High

>80

mg/dL

Also reported in: mmol/L

BUN is a waste product filtered by the kidneys. Normal levels mean the kidneys are filtering blood properly.

Low

Low BUN is often seen with low-protein diets, liver dysfunction, or increased fluid intake.

What to do:

Discuss your dog's diet and liver health with your vet.

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Canine BUN: 5 mg/dL (Low)

Normal

BUN is a waste product filtered by the kidneys. Normal levels mean the kidneys are filtering blood properly.

What to do:

No action needed.

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Canine BUN: 15 mg/dL

High

High BUN can indicate kidney disease, dehydration, or a high-protein diet.

What to do:

Your vet will likely check creatinine and urine specific gravity to confirm if the issue is kidney-related or just dehydration.

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Canine BUN: 35 mg/dL (High)

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