A urea blood test, also known as a blood urea nitrogen (BUN) test, measures the amount of urea nitrogen in your blood. Urea is a waste product produced by your body when it breaks down protein. Your kidneys filter urea from your blood and eliminate it in your urine.
A high BUN level can indicate that your kidneys are not working properly, as they are unable to effectively filter urea from your blood. Other factors, such as dehydration, a high protein diet, or certain medical conditions like heart failure, can also lead to elevated BUN levels.
A low BUN level, while less common, can be a sign of liver disease or malnutrition.
This test is often ordered as part of a routine checkup, or when a doctor suspects a problem with your kidneys or liver.
