A urea nitrogen blood test, also known as a blood urea nitrogen (BUN) test, is a common diagnostic tool used to evaluate kidney function. The test measures the level of urea nitrogen in your blood, which is a waste product produced by your body when it breaks down protein. Urea is filtered out of your blood by your kidneys and excreted in your urine. If your kidneys are not functioning properly, urea can build up in your blood, leading to a range of health problems.
The BUN test is often ordered as part of a routine check-up or to monitor kidney function in individuals with known kidney disease. It is usually performed in conjunction with other tests, such as a creatinine test, to provide a more comprehensive picture of kidney function.
Interpreting Your Urea Nitrogen Blood Test Results
Urea nitrogen blood test results are typically reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). The normal range for BUN levels varies slightly depending on the laboratory and the individual's age and sex. Generally, a normal BUN level is between 6 and 24 mg/dL (2.1 to 8.5 mmol/L).
A BUN level that is higher than normal may indicate:
- Kidney disease or damage
- Dehydration
- High-protein diets
- Medications that can affect kidney function, such as certain antibiotics and steroids
- Certain medical conditions, such as heart failure or liver disease
On the other hand, a BUN level that is lower than normal may indicate:
- Liver disease
- Malnutrition
- Overhydration
Factors That Can Affect BUN Levels
Several factors can affect BUN levels, including:
| Factor | Effect on BUN Levels |
|---|---|
| Age | BUN levels tend to increase with age |
| Diet | A high-protein diet can increase BUN levels |
| Hydration status | Dehydration can increase BUN levels, while overhydration can decrease them |
| Medications | Certain medications, such as diuretics and certain antibiotics, can affect BUN levels |
Key Points
- A urea nitrogen blood test measures the level of urea nitrogen in your blood, which is a waste product produced by your body when it breaks down protein.
- A BUN level that is higher than normal may indicate kidney disease or damage, dehydration, high-protein diets, certain medications, or certain medical conditions.
- A BUN level that is lower than normal may indicate liver disease, malnutrition, or overhydration.
- Several factors can affect BUN levels, including age, diet, hydration status, and medications.
- Abnormal BUN levels should be evaluated by a healthcare professional to determine the underlying cause and develop a plan to manage kidney function.
What to Do Next
If you have received abnormal BUN test results, it is essential to consult with your doctor to determine the underlying cause and develop a plan to manage your kidney function. Your doctor may recommend additional testing, such as a creatinine test or imaging studies, to evaluate your kidney function and diagnose any underlying conditions.
In the meantime, there are several steps you can take to support kidney health, including:
- Staying hydrated by drinking plenty of water
- Eating a balanced diet that is low in protein and salt
- Avoiding certain medications that can affect kidney function
- Managing underlying medical conditions, such as diabetes and high blood pressure
What does a high BUN level mean?
+A high BUN level can indicate kidney disease or damage, dehydration, high-protein diets, certain medications, or certain medical conditions.
What does a low BUN level mean?
+A low BUN level can indicate liver disease, malnutrition, or overhydration.
How can I lower my BUN level?
+To lower your BUN level, you can try staying hydrated, eating a balanced diet, avoiding certain medications, and managing underlying medical conditions.