What is the normal range for blood urea nitrogen (BUN) levels?

The normal range for blood urea nitrogen (BUN) levels is considered to be between 5 and 20 mg/dL, which aligns with the choice provided. BUN is a measurement of the amount of nitrogen in the blood that comes from the waste product urea, which is formed in the liver during protein metabolism and excreted by the kidneys. This range is important for assessing kidney function, as elevated levels can indicate impaired kidney function or increased protein breakdown, while lower levels may suggest liver dysfunction or malnutrition.

Understanding this range is crucial in clinical practice, as it helps healthcare providers detect and monitor various medical conditions. For instance, when a patient's BUN levels fall outside this normal range, it could trigger further diagnostic testing to investigate underlying issues.