A BUN, or blood urea nitrogen test, can provide important information about your kidney

function. The main job of your kidneys is to remove waste and extra fluid from your body. If

you have kidney disease, this waste material can build up in your blood and may lead to

serious health problems, including high blood pressure, anemia, and heart disease.The test

measures the amount of urea nitrogen in your blood. Urea nitrogen is one of the waste

products removed from your blood by your kidneys. Higher than normal BUN levels may be

a sign that your kidneys aren't working efficiently.