Reviewed: 16. April 2026
BUN Blood Urea Nitrogen (BUN)
Unit: mg/dl
Quick Explanation
Blood urea nitrogen (BUN) is produced when protein is broken down and excreted by the kidneys. Elevated levels may indicate reduced kidney function or a high-protein diet. Discuss abnormal findings with your doctor.
📊 Reference Values
ℹ️ Reference ranges may vary slightly between laboratories. Always compare your value with the reference range from your own lab report.
🔍 Possible Causes
Value too high — possible causes
- ·Kidney disease
- ·Dehydration
- ·High-protein diet
- ·Gastrointestinal bleeding
Value too low — possible causes
- ·Malnutrition
- ·Liver disease
- ·Overhydration
This list shows possible causes — not a diagnosis. Only your doctor can correctly interpret your result.
🩺 Questions for Your Doctor
- →Is my BUN related to my kidney function?
- →Should I adjust my protein intake?
- →Do I need further kidney tests?
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Medical Disclaimer
The content on this page is for general information only and does not replace professional medical advice, diagnosis, or treatment. Always consult your doctor or pharmacist for health-related questions. Lab values should always be assessed in the context of your personal medical history.