Blood urea nitrogen (BUN) is ablood testperformed as a marker of kidney function.
It is part of the basic or comprehensive metabolic panel done for health screening.
It is also used to monitor the progression of kidney failure.
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BUN is produced by the breakdown of protein and usually cleared from the blood by the kidneys.
A higher than normal value may show impaired kidney function.
What Is Blood Urea Nitrogen (BUN)?
BUN is a waste product of cell metabolism.
This produces nitrogen-containing ammonia as a byproduct, which is excreted into the bloodstream.
The liver transforms ammonia into urea to make it less toxic and sends the urea out into the bloodstream.
Urea is filtered out of the blood by the kidneys.
The BUN level in the blood is, therefore, stable.
This panel is typically run during health screenings and in monitoring diabetes management.
Purpose of Test
The purpose of the BUN test is to assess kidney function.
Before the Test
You do not need any special preparation to take this test.
Interpreting Results
BUN in Diabetes Management
Kidney failure is a complication of diabetes.
BUN may also be monitored if you are given drugs that may impair kidney function.
For example, elevated BUN levels brought on by dehydration indicate that a person needs to drink more fluids.
More serious implications of abnormal BUN levels may result in additional testing or referral to a specialist.
Be sure to discuss your results with your healthcare provider.
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