Urea nitrogen is a waste product that’s created in the liver when the body breaks down proteins. Normally, the kidneys filter out this waste and urinating removes it from the body. https://www.healthline.com/health/bun
A common blood test, the blood urea nitrogen ( BUN ) test reveals important information about how well your kidneys and liver are working. A BUN test measures the amount of urea nitrogen that’s in your blood.
The BUN test doesn’t require any special preparation. However, it’s important to tell your doctor if you’re taking any prescription or over-the-counter medications. Certain medications can affect your BUN levels. Some medications, including chloramphenicol or streptomycin, may lower your BUN levels. Other drugs, such as antibiotics and diuretics, may increase your BUN levels.
BUN levels tend to increase when the kidneys or liver are damaged. Having too much urea nitrogen in the blood or having high BUN levels can be a sign of kidney or liver problems.In general, normal BUN levels fall in the following ranges: adult men: 8 to 20 mg/dL, adult women: 6 to 20 mg/dL, children: 5 to 18 mg/dL.